US20090000173A1 - Firearm - Google Patents

Firearm Download PDF

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Publication number
US20090000173A1
US20090000173A1 US12/208,162 US20816208A US2009000173A1 US 20090000173 A1 US20090000173 A1 US 20090000173A1 US 20816208 A US20816208 A US 20816208A US 2009000173 A1 US2009000173 A1 US 2009000173A1
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US
United States
Prior art keywords
barrel
bolt
firearm
receiver
upper receiver
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US12/208,162
Inventor
Alexander J. Robinson
Darin G. Nebeker
Jon C. Holway
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
RMDI LLC
Original Assignee
RMDI LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US10/911,963 external-priority patent/US7596900B2/en
Application filed by RMDI LLC filed Critical RMDI LLC
Priority to US12/208,162 priority Critical patent/US20090000173A1/en
Assigned to RMDI, L.L.C. reassignment RMDI, L.L.C. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HOLWAY, JON C., NEBEKER, DARIN G., ROBINSON, ALEXANDER J.
Assigned to RMDI, L.L.C. reassignment RMDI, L.L.C. CORRECTIVE ASSIGNMENT TO CORRECT THE ASSIGNEE'S ADDRESS PREVIOUSLY RECORDED ON REEL 021509 FRAME 0940. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNMENT OF US PATENT APPLICATION NO. 12/208,162, FILED SEPTEMBER 10, 2008, TO RMDI, L.L.C.. Assignors: HOLWAY, JON C., NEBEKER, DARIN G., ROBINSON, ALEXANDER J.
Publication of US20090000173A1 publication Critical patent/US20090000173A1/en
Abandoned legal-status Critical Current

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A21/00Barrels; Gun tubes; Muzzle attachments; Barrel mounting means
    • F41A21/48Barrel mounting means, e.g. releasable mountings for replaceable barrels
    • F41A21/485Barrel mounting means, e.g. releasable mountings for replaceable barrels using screws or bolts
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A11/00Assembly or disassembly features; Modular concepts; Articulated or collapsible guns
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A15/00Cartridge extractors, i.e. devices for pulling cartridges or cartridge cases at least partially out of the cartridge chamber; Cartridge ejectors, i.e. devices for throwing the extracted cartridges or cartridge cases free of the gun
    • F41A15/12Cartridge extractors, i.e. devices for pulling cartridges or cartridge cases at least partially out of the cartridge chamber; Cartridge ejectors, i.e. devices for throwing the extracted cartridges or cartridge cases free of the gun for bolt-action guns
    • F41A15/14Cartridge extractors, i.e. devices for pulling cartridges or cartridge cases at least partially out of the cartridge chamber; Cartridge ejectors, i.e. devices for throwing the extracted cartridges or cartridge cases free of the gun for bolt-action guns the ejector being mounted on or within the bolt; Extractors per se
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A17/00Safety arrangements, e.g. safeties
    • F41A17/42Safeties for locking the breech-block or bolt in a safety position
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A17/00Safety arrangements, e.g. safeties
    • F41A17/74Hammer safeties, i.e. means for preventing the hammer from hitting the cartridge or the firing pin
    • F41A17/76Hammer safeties, i.e. means for preventing the hammer from hitting the cartridge or the firing pin automatically operated, i.e. operated by breech opening or closing movement
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A19/00Firing or trigger mechanisms; Cocking mechanisms
    • F41A19/06Mechanical firing mechanisms, e.g. counterrecoil firing, recoil actuated firing mechanisms
    • F41A19/42Mechanical firing mechanisms, e.g. counterrecoil firing, recoil actuated firing mechanisms having at least one hammer
    • F41A19/43Mechanical firing mechanisms, e.g. counterrecoil firing, recoil actuated firing mechanisms having at least one hammer in bolt-action guns
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A3/00Breech mechanisms, e.g. locks
    • F41A3/12Bolt action, i.e. the main breech opening movement being parallel to the barrel axis
    • F41A3/14Rigid bolt locks, i.e. having locking elements rigidly mounted on the bolt or bolt handle and on the barrel or breech-housing respectively
    • F41A3/16Rigid bolt locks, i.e. having locking elements rigidly mounted on the bolt or bolt handle and on the barrel or breech-housing respectively the locking elements effecting a rotary movement about the barrel axis, e.g. rotating cylinder bolt locks
    • F41A3/26Rigid bolt locks, i.e. having locking elements rigidly mounted on the bolt or bolt handle and on the barrel or breech-housing respectively the locking elements effecting a rotary movement about the barrel axis, e.g. rotating cylinder bolt locks semi-automatically or automatically operated, e.g. having a slidable bolt-carrier and a rotatable bolt
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A3/00Breech mechanisms, e.g. locks
    • F41A3/12Bolt action, i.e. the main breech opening movement being parallel to the barrel axis
    • F41A3/36Semi-rigid bolt locks, i.e. having locking elements movably mounted on the bolt or on the barrel or breech housing
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A3/00Breech mechanisms, e.g. locks
    • F41A3/64Mounting of breech-blocks; Accessories for breech-blocks or breech-block mountings
    • F41A3/66Breech housings or frames; Receivers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A3/00Breech mechanisms, e.g. locks
    • F41A3/64Mounting of breech-blocks; Accessories for breech-blocks or breech-block mountings
    • F41A3/70Anti-rebound arrangements, i.e. preventing rebound of the bolt out of the firing position
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A5/00Mechanisms or systems operated by propellant charge energy for automatically opening the lock
    • F41A5/02Mechanisms or systems operated by propellant charge energy for automatically opening the lock recoil-operated
    • F41A5/10Mechanisms or systems operated by propellant charge energy for automatically opening the lock recoil-operated having a movable inertia weight, e.g. for storing energy
    • F41A5/12Mechanisms or systems operated by propellant charge energy for automatically opening the lock recoil-operated having a movable inertia weight, e.g. for storing energy mounted in a gun having a fixed barrel
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A5/00Mechanisms or systems operated by propellant charge energy for automatically opening the lock
    • F41A5/18Mechanisms or systems operated by propellant charge energy for automatically opening the lock gas-operated
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41AFUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE
    • F41A5/00Mechanisms or systems operated by propellant charge energy for automatically opening the lock
    • F41A5/18Mechanisms or systems operated by propellant charge energy for automatically opening the lock gas-operated
    • F41A5/24Mechanisms or systems operated by propellant charge energy for automatically opening the lock gas-operated by direct action of gas pressure on bolt or locking elements

Definitions

  • the present invention relates to firearms. More specifically, the present invention relates to firearms that can be quickly configured with a minimum of additional parts to fire different calibers of ammunition with improved reliability in harsh environmental and firing conditions.
  • receivers for firearms that include guidance features, such as internal rails, within a passageway tend to require significant effort to assemble. Often the rails are first manufactured and then attached to the receiver through welding or mechanical fasteners. Alternatively, the receiver is made in halves with integrally formed rails and then the halves are then welded together.
  • Some currently available firearms are able to fire different calibers of cartridges.
  • these firearms all use the same size ejection port for each caliber, which may lead to problems with ejection.
  • the ejection port may be too large so that the spent cartridge is ejected in a random pattern. This random ejection pattern may lead to lost brass as well as user frustration as the brass may be ejected rearward into the user of the firearm.
  • the ejection port is functional but slightly too small, the spent cartridge may fail to entirely eject from the firearm which may raise reliability issues.
  • firearms that are able to fire different calibers of cartridges use the same ejector in the same location for all calibers, which can also lead to ejection problems with certain calibers or entirely prevent a firearm designed to fire one caliber from firing larger or smaller cartridges.
  • the ejector for a firearm designed to fire a 5.56 NATO cartridge may be unable to fire a Springfield 30.06 cartridge because the ejector is disposed too close to the barrel.
  • the firearm of the invention may be used to fire a cartridge that includes a base.
  • the firearm generally includes a barrel having a chamber, a receiver, a bolt supported by the receiver; and a fire control group.
  • the firearm may also include a firing pin.
  • the fire control group may include a hammer, trigger, a bolt hold open device, a disconnect, an auto sear, and a fire selector/safety switch device.
  • the firearm may also include a firing pin that is guided by the bolt.
  • the receiver may be a two piece receiver that includes a lower receiver containing the fire control group and an integrally formed upper receiver that may include a longitudinal axis, a passageway extending generally parallel to the longitudinal axis, and a guidance feature extending into the passageway and along the passageway generally parallel to the longitudinal axis.
  • the guidance feature may be an internal rail that guides the movement of the bolt within the upper receiver.
  • the upper receiver and its guidance feature and passageway are formed by extrusion.
  • the upper receiver may include a second passage way that is formed as the upper receiver is extruded. Extrusion permits the formation of multiple features in one processing step, which can minimize machining and assembly time and reduce manufacturing costs.
  • the upper receiver may be extruded with an accessory rail that extends parallel to the longitudinal axis.
  • the accessory rail may be extruded at the 3, 6, 9, & 12 o'clock positions.
  • the upper receiver extrusion may be cut to size and then machined to provide additional features.
  • the integrally formed upper receiver may include a charging handle slot that is machined into the upper receiver and the extruded accessory rail may be machined to provide additional detail and utility to the accessory rail.
  • the barrel may be attached to the receiver or where a two piece receiver is used, the barrel may be attached to the upper receiver.
  • the barrel may include a barrel extension with locking features for locking the bolt against the chamber.
  • the barrel extension may also include a beveled barrel retention recess.
  • a barrel attachment device For attaching the barrel to the receiver, a barrel attachment device may be used.
  • the barrel attachment device may have a threaded section and a tapered end. Additionally, the angle of the tapered end may be the reciprocal of the angle of the beveled barrel retention recess.
  • the upper receiver may include a barrel retention feature that allows the barrel attachment device to be disposed in the barrel retention feature.
  • the barrel retention feature may be threaded to allow the threaded section of the barrel attachment device to engage the barrel retention feature so that the tapered end engages the beveled barrel retention recess to attach the barrel to the upper receiver.
  • the bolt may be connected to a bolt carrier.
  • the bolt carrier may be supported by the upper receiver and may be guided by the guidance feature of the upper receiver.
  • the bolt carrier may include an operating rod slot that is open at an end of the bolt carrier and a cam slot that extends from the operating rod slot.
  • the bolt may include a protrusion that extends from the bolt and into the cam slot so that the protrusion is movable within the cam slot.
  • the bolt carrier may also include a safety extension disposed below the bolt.
  • the safety extension of the bolt carrier prevents the hammer from striking the firing pin until the bolt is fully locked against the chamber.
  • the safety extension may also include an auto trip. The auto trip engages the auto sear to allow for fully automatic fire of the firearm.
  • the bolt carrier may also include a forward assist feature that may be selectively engaged by a forward assist device of a non-reciprocating charging handle.
  • the forward assist device of the charging handle is used to selectively engage the forward assist feature of the bolt carrier to provide manual locking of the bolt against the chamber.
  • the bolt may further include a bolt face and at least two lugs for locking the bolt face against the chamber of the barrel.
  • the lugs of the bolt may be disposed within the barrel extension and abut the locking features of the barrel extension in order to close an end of the chamber with the bolt face allowing the firearm to be safely fired.
  • the bolt may also include an ejector access groove, a sliding extractor, and a polymer spring that biases the sliding extractor against the base of the cartridge to retain the base of the cartridge against the bolt face.
  • the ejector access groove permits the bolt to move past an ejector so that the ejector may dislodge a cartridge from the bolt face.
  • a polymer spring provides the advantage over metal springs that a polymer spring may be much smaller, and yet provide the same force as a larger metal spring. Therefore, a polymer spring permits smaller assemblies to be used that are not otherwise possible.
  • the bolt includes a plane that extends through the middle of the bolt face and perpendicular to the bolt face.
  • the sliding extractor may be disposed at an angle ranging from about thirty degrees to about fifteen degrees from the plane extending through the middle of the bolt face.
  • the sliding extractor may be disposed at an angle ranging from about twenty-five degrees to about twenty degrees from the plane extending through the middle of the bolt face.
  • the extractor further includes an extractor head. As the bolt is locked within the barrel extension, the extractor head engages the support surface to support the extractor against the base of a cartridge. Having the support surface directly support the extractor helps to prevent mechanical failure of the extractor where abnormally high pressure occurs in the chamber during the firing of a cartridge.
  • the bolt may be rotated in a direction along the shortest distance from the feed lug to the extractor about the bolt face to lock the bolt face against the chamber or in other words, to close the chamber and allow the firearm to be safely discharge the cartridge.
  • the bolt may also be rotated counter-clockwise to lock against the chamber as viewed from the bolt to the barrel.
  • the direction of bolt rotation can affect the angle of ejection of spent cartridges from the firearm, as well as the size and placement of lugs, extractor, and other features of the bolt.
  • the counter-clockwise rotation of the bolt allows the use of three large lugs and a large extractor disposed at approximately 20 degrees from the plane about the bolt face.
  • the protrusion may be connected to the bolt carrier by an operating rod.
  • the operating rod may include a piston and a foot.
  • the foot of the operating rod is disposable within the operating rod slot of the bolt carrier to prevent the bolt from separating from the bolt carrier and to connect the operating rod to the bolt carrier. More specifically, the foot of the operating rod is seated within the operating rod slot of the bolt carrier, which prevents the protrusion of the bolt from sliding out of the cam slot of the bolt carrier.
  • the bolt is slidably connected to the bolt carrier.
  • the operating rod may further include an anti-bounce mechanism. As the bolt in some firearms is closed against the chamber, the force is great enough that the bolt carrier bounces so that the firearm may not function reliably. The anti-bounce mechanism counteracts this tendency to bounce.
  • the anti-bounce mechanism of the operating rod includes a cavity disposed within the operating rod and one or more weights movable within the cavity. Specifically, once the bolt closes on the chamber, the weight moves within the cavity to be stopped at a end of the cavity. The transfer of energy from the weight to the operating rod and consequently to the bolt and the bolt carrier counteracts the bounce to keep the bolt carrier properly positioned against the chamber.
  • the fire control group may be connected to the lower receiver of the firearm.
  • the lower receiver may also include an attachment structure.
  • the attachment structure is used to attach the lower receiver to the upper receiver.
  • the firearm may also include a recoil spring assembly disposed proximate the operating rod.
  • the recoil spring assembly may be alternatively connected to the operating rod, the bolt carrier, the bolt, or the piston.
  • the recoil spring assembly may include a mating attachment structure and a disassembly button.
  • the mating attachment structure is attached to the attachment structure of the lower receiver to attach the lower receiver to the upper receiver.
  • the disassembly button may be actuated to detach the mating attachment structure from the attachment structure in order to detach the lower receiver from the upper receiver.
  • the disassembly button may be disposed on a lateral side of the upper receiver so that the upper receiver may include an accessory rail that extends the complete length of the upper receiver.
  • the ejector of the firearm may be attachable to the receiver at a plurality of locations. Having an ejector that is removably attachable to the receiver at a plurality of locations permits the firearm to accommodate different cartridge sizes. Specifically, adjusting the position of the ejector affects how a spent cartridge is ejected from the firearm.
  • the firearm in some configurations may also include an ejection buffer attachable to the receiver at a plurality of locations.
  • the ejection buffer may be used to adjust the size of the ejection port of the firearm which also helps to permit the firearm to accommodate different cartridge sizes. For example, if the ejection port is too large, the spent cartridge may eject rearward toward the user of the firearm. If the ejection port is too small, the spent cartridge will fail to discharge, causing the firearm to fail.
  • the invention also includes a method for manufacturing an integrally formed upper receiver.
  • the method includes the steps of extruding an upper receiver having a passageway and a guidance feature disposed in the passageway, and machining the upper receiver to form a barrel attachment feature.
  • the guidance feature may be a slot that extends out of the passageway, such as a slot or groove.
  • the upper receiver may also be extruded to include an accessory rail and a second passageway that is a gas tube hole.
  • the method may also include the steps of machining the accessory rail to provide grooves that extend perpendicular to the length of the accessory rail and machining a charging handle slot and a charging handle access groove into the upper receiver. Additionally, the method may include the step of machining the passageway and the second passage way to form a bolt carrier cavity.
  • the invention includes a method for changing the caliber of a firearm with caliber conversion parts.
  • the firearm includes at least a receiver, a barrel attached to the receiver, and an ejection buffer that is attachable to the upper receiver at a plurality of locations.
  • the caliber conversion parts include at least a second barrel.
  • the method includes the steps of removing the barrel from the upper receiver, attaching the second barrel to the upper receiver, detaching the ejection buffer from the upper receiver at a first location, and attaching the ejection buffer to the upper receiver at a second location.
  • the firearm further includes a bolt connected to a bolt carrier, an operating rod connected to the bolt carrier, wherein the bolt, bolt carrier, and operating rod are disposed within the firearm and the caliber conversion parts include a second bolt
  • the method may also include the steps of removing the bolt, bolt carrier, and operating rod from the firearm, disconnecting the operating rod from the bolt carrier to allow removal of the bolt from the bolt carrier, removing the bolt from the bolt carrier, disposing the second bolt in the bolt carrier, connecting the operating rod to the bolt carrier to prevent removal of the second bolt from the bolt carrier, and disposing the second bolt, bolt carrier, and operating rod in the firearm.
  • the firearm may include furniture such as a hand guard, a butt stock, and a pistol grip.
  • the hand guard may be attached to the firearm proximate the barrel.
  • the butt stock and pistol grip may be attached to the receiver or in some configurations, the lower receiver.
  • the firearm may also include a feed attachment device such as a magazine well or belt feed mechanism.
  • FIG. 1 is a side elevation view of a firearm according to the invention
  • FIG. 2 is a rear elevation view of the upper receiver of the firearm as extruded
  • FIG. 3 is a rear elevation view of the finished upper receiver of FIG. 2 ;
  • FIG. 4 is a perspective view of a cross section taken along Section 3 - 3 of the
  • FIG. 5 is a perspective view of the lower receiver containing components of the fire control group
  • FIG. 6 is an exploded side elevation view of the operating system of the firearm
  • FIG. 7 is an exploded perspective view of a bolt of firearm
  • FIG. 8 is a cross section view along Section 8 - 8 of FIG. 6 of the bolt engaging a barrel extension of the firearm;
  • FIG. 9 is a cross section view along Section 8 - 8 of FIG. 6 of the bolt locked within the barrel extension;
  • FIG. 10 is a perspective view of a bolt carrier according to the invention.
  • FIG. 11 is an alternative perspective view of a bolt carrier according to the invention.
  • FIG. 12 is a cross section view of the operating rod of FIG. 6 that includes an anti-bounce mechanism
  • FIG. 13 is a side elevation view of a recoil spring assembly
  • FIG. 14 is a side elevation view of a non-reciprocating charging handle with forward assist capability.
  • the phrases “connected to,” “coupled to,” and “in communication with” refer to any form of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, and thermal interaction.
  • the phrase “attached to” refers to a form of mechanical coupling that restricts relative translation or rotation between the attached objects.
  • butting refers to items that are in direct physical contact with each other, although the items may not be attached together.
  • integrated refers to a body that is manufactured integrally, i.e., as a single piece, without requiring the assembly of multiple pieces. Multiple parts may be integrally formed with each other if they are formed from a single work piece. Thus, parts that are welded or otherwise fastened together are not integrally formed.
  • a side elevation view illustrates a firearm 10 according to the invention.
  • the firearm 10 includes a receiver 12 that includes an upper receiver 14 and a lower receiver 16 .
  • the upper receiver 14 may be integrally formed with accessory rails 18 and an ejection port 20 for allowing spent cartridges (not shown) from the firearm 10 .
  • the firearm 10 also includes a barrel 22 that is attached to the upper receiver 14 .
  • the firearm 10 may also include a front sight 24 , a rear sight 26 , hand guards 28 , and a flash hider 30 .
  • the firearm 10 may include vertical grips, a grenade launcher, a bayonet lug, a muzzle brake, a scope, a red dot sight, a rangefinder, a silencer, a light system, a laser, or other accessories known in the art.
  • the hand guards 28 are shown attached to the integral accessory rail system 18 and may be removed as desired by a user.
  • the lower receiver 16 may be attached to a butt stock 32 and a pistol grip 34 .
  • a fire control group 36 including a trigger 38 , a selector/safety switch 40 , and a bolt hold open device 44 are coupled to the lower receiver 16 in this configuration.
  • the fire control group may be coupled to the receiver 12 or the upper receiver 14 .
  • the lower receiver 16 may be integrally formed with a magazine well 46 for receiving a magazine (not shown). Alternatively, the magazine well, cartridge feeding device, or a belt feed device (not shown) may be separately formed and connected to the firearm.
  • the upper receiver 14 and the lower receiver 16 are pivotally coupled by a receiver pin 50 .
  • the receiver pin 50 allows the upper receiver 14 to be pivoted away from the lower receiver 16 providing access to internal components for cleaning and maintenance.
  • the firearm 10 also includes an ejection buffer 52 attachable to the upper receiver 14 at a plurality of locations.
  • the ejection buffer 52 is used to adjust the size of the ejection port as well as to better control the direction of ejection of spent cartridges. More specifically, the ejection buffer may be attached at a first location 54 or at a second location 56 or at any location in between the first location 54 and the second location 56 , depending on the caliber of cartridge that a user desires to fire from the firearm 10 .
  • the first location 54 may be used for calibers with smaller cartridges and the second location 56 may be used for larger cartridges.
  • a rear elevation view illustrates the upper receiver 14 of the firearm 10 of FIG. 10 .
  • the upper receiver 14 may be initially formed by extrusion and may be made of aluminum or steel. Alternatively, the upper receiver 14 may be made of any plastic, composite, ceramic, or metal that is relatively tough and wear resistant. Extruding the upper receiver 14 permits several features of the upper receiver 14 to be formed at the time of extrusion, which lowers manufacturing costs and production time. Additionally, extruding the upper receiver 14 provides the upper receiver 14 with a natural longitudinal is so that the features formed during extrusion extend generally parallel to the longitudinal axis.
  • the upper receiver 14 is extruded to include the accessory rails 18 , a first passageway 60 , a second passageway 62 , and guidance features 64 .
  • the guidance features 64 extend into the passageway and along the passageway to help guide a bolt (shown in FIG. 6 ) or a bolt carrier (shown in FIG. 6 ) through the first passageway 60 of the receiver 12 .
  • the guidance features 64 as shown include internal rails 65 and shoulders 66 that are used to guide the movement of internal components of the firearm 10 .
  • the accessory rails 18 include a rail at the 12 o'clock position 67 , the 3 o'clock position 68 , the 6 o'clock position 69 , and the 9 o'clock position 70 .
  • An advantage of extruding the features of the upper receiver 14 is that the features formed by extrusion are generally straight and parallel to each other. Otherwise assembly may result in a great deal of variation.
  • a rear elevation view shows the finished upper receiver 14 of FIG. 2 .
  • various machining methods known in the art such as drilling, tapping, milling, etc., are used to form other integral features of the upper receiver 14 .
  • the upper receiver 14 when finished may include a charging handle slot 71 , a operating rod cavity 72 , a disassembly button attachment point 74 , and other features known in the art that enhance the functional and aesthetic qualities of the upper receiver 14 .
  • the upper receiver 14 also has a lateral direction 76 and a vertical direction 78 .
  • the disassembly button attachment point 74 disposes a disassembly button (shown in FIG. 13 ) on a lateral 76 side of the upper receiver 14 .
  • the disassembly button (shown in FIG. 13 ) permits the upper receiver 14 to be selectively detached and attached to the lower receiver 16 shown in FIG. 1 .
  • By disposing the disassembly button attachment point 74 on the lateral 76 side of the upper receiver 14 a user may grip the upper receiver and slide the disassembly button (shown in FIG. 13 ) to detach the upper receiver 14 from the lower receiver 16 of FIG. 1 .
  • the upper receiver 14 includes a bottom cut 79 that allows the fire control group 36 and other components of the lower receiver 16 to interact with the components connected to the upper receiver 14 .
  • FIG. 4 a perspective view of a cross section taken along Section 3 - 3 illustrates the finished upper receiver 14 of FIG. 3 .
  • the first passageway 60 , the second passageway 62 , the guidance features 64 extend generally parallel to a longitudinal axis 80 .
  • the operating rod cavity 72 also extends generally parallel to the longitudinal axis 80 and midway into the upper receiver 14 .
  • the accessory rail 18 has been machined to provide grooves 82 that extend perpendicular to the longitudinal axis 80 so that the accessory rail 18 as shown is a 1913 type accessory rail.
  • Lightening cuts 84 have also been made in the upper receiver 14 in order to reduce the weight of the upper receiver 14 .
  • the upper receiver 14 also includes a barrel attachment feature 86 that may be a threaded hole 88 .
  • a pivot hole 90 has also been machined that allows the upper receiver 14 to pivot around the receiver pin 50 (shown in FIG. 1 ).
  • a plurality of holes 92 have also been cut to provide for the attachment of an ejector 94 to the upper receiver at a plurality of locations. More specifically, the ejector may be attached at a first location 96 or a second location 98 .
  • the first location 96 may be used for calibers with smaller cartridges and the second location 98 may be used for larger cartridges.
  • the upper receiver 14 also includes a charging handle access groove 99 that permits a charging handle (shown in FIG. 14 ) disposed in the charging handle slot 71 to access the interior of the upper receiver 14 .
  • FIG. 5 a perspective view illustrates the lower receiver 16 containing components of the fire control group 36 .
  • the lower receiver 16 includes a pivot hole 100 that allows the lower receiver 16 to pivot around the receiver pin 50 (shown in FIG. 1 ).
  • the lower receiver 16 also includes an attachment structure 102 for attaching the lower receiver 16 to the upper receiver 14 of FIG. 1 .
  • the lower receiver 16 includes a pocket 103 that will be described below in relation to FIG. 6 .
  • the attachment structure 102 is a hole that engages a mating attachment structure (shown in FIG. 13 ) that is connected to the upper receiver 14 of FIG. 1 .
  • the lower receiver 16 is shown integrally formed with a magazine well 46 for receiving a magazine (not shown).
  • the magazine well 46 includes a magazine release 104 that operates a magazine catch 106 that retains the magazine (not shown) in the magazine well 46 .
  • the lower receiver 16 may be made of plastic, metal, ceramic, or composite. Furthermore, the lower receiver 16 may be manufactured by injection molding, casting, machining, or any other manufacturing process known in the art.
  • the fire control group 36 includes a trigger 38 , a selector/safety switch 40 , and a bolt hold open device 44 .
  • the fire control group 36 also includes a hammer 108 and an auto sear 1 10 .
  • the hammer 108 is used to impart kinetic energy to a firing pin (shown in FIG. 6 ) when the trigger 38 is pulled or for fully automatic firing of the firearm 10 when the trigger 38 is pulled and the auto sear 110 is tripped.
  • the hammer 108 is in a set position that is ready to strike the firing pin (not shown).
  • the hammer 108 pivots about a pin 112 and a head 114 of the hammer 108 strikes an end of the firing pin (shown in FIG. 6 ).
  • the hammer 108 also includes a neck 116 that increases the angular momentum of the head 116 .
  • FIG. 6 is an exploded side elevation view of the operating system 120 of the firearm 10 of FIG. 1 .
  • the operating system 120 includes the barrel 22 having a chamber 122 , a bolt 124 , a bolt carrier 126 , an operating rod 128 , a recoil spring assembly 130 , a gas tube 132 .
  • the barrel 22 may include a gas block 134 , and a barrel extension 136 and is shown attached to the gas block 134 and the barrel extension 136 .
  • the barrel 22 may be attached to the gas block 134 and the barrel extension 136 by welding, pinning, brazing, threading, and other methods known in the art.
  • a propellant disposed within the cartridge is burned to produce gas and increase the pressure within the chamber 122 .
  • the high pressure gas then pushes a bullet (not shown) out of the barrel 22 toward a target.
  • the high pressure gas flows through the barrel 22 from the chamber 122 toward the gas block 134 .
  • the high pressure gas exits the barrel 22 through a hole (not shown) in the barrel 22 and into the gas block 134 .
  • the gas block 134 directs the gas into the gas tube 132 .
  • the gas tube 132 is disposed within the second passageway 62 of the upper receiver 14 .
  • the second passageway 62 is the gas tube 132 and directly connected to the gas block 134 .
  • the operating rod 128 includes a piston 140 , a recoil tube 142 , and a foot 144 .
  • the piston 140 is disposed within the gas tube 132 proximate the gas block 134 . As the high pressure gas enters the gas tube, the high pressure gas pushes the piston 140 away from the gas block 134 .
  • the gas tube 132 includes vent holes 146 that help to prevent the high pressure gas from entering the operating rod cavity 72 of the upper receiver 14 (shown in FIG. 4 ). The high pressure gas is able then able to exit the firearm through the lightening cuts 84 (shown in FIG. 4 ) from the vent holes 146 . Where the second passageway 62 is the gas tube 132 , the gas vents directly through the lightening cuts 84 (shown in FIG. 4 ).
  • Preventing the high pressure gas from entering the operating rod cavity 72 of the upper receiver 14 can be important because the high pressure gas deposits carbon, powder residue, and lead on the surfaces of the firearm 10 that the high pressure gas comes into contact with. These deposits can lead to firearm malfunctions, such as jamming, feeding problems, and ejection failures.
  • the recoil spring assembly 130 includes a spring 148 surrounding a guide rod 150 and a sliding rod 152 .
  • the recoil spring assembly 130 is connected to the operating rod 128 by being partially disposed within the recoil tube 142 of the operating rod 128 .
  • the recoil spring assembly 130 may be connected to the bolt carrier 126 or the bolt 124 .
  • the recoil spring assembly 130 is compressed and stores the kinetic energy of the moving operating rod 128 as potential energy in the spring 148 as the sliding rod 150 slides within the guide rod 150 .
  • the operating rod 128 is connected to the bolt carrier 126 .
  • the bolt carrier 126 carries the bolt 124 through the upper receiver 14 of FIG. 4 to lock or abut the bolt 124 against the chamber 122 . Because the bolt carrier 126 is connected to the bolt 124 , the bolt 124 moves as the bolt carrier 126 moves. Thus, as the operating rod 128 moves away from the gas block 134 in reaction to the high pressure gas, the bolt carrier 126 moves the bolt 124 to unlock from barrel extension 136 and from against the chamber 122 .
  • the bolt 124 removes the spent cartridge (shown in FIG. 7 ) from the chamber 122 .
  • the bolt 124 moves past the ejector 94 of FIG. 4 so that the ejector 94 strikes the spent cartridge (shown in FIG. 7 ) to knock the spent cartridge from the bolt 124 and eject the spent cartridge through the ejection port 20 and out of the firearm 10 shown in FIG. 1 .
  • the bolt 124 and bolt carrier 126 contact the head 114 of the hammer 108 (shown in FIG. 5 ) to place the hammer 108 in the set position as shown in FIG. 5 .
  • the bolt 124 may be stopped by the bolt hold open device 44 (shown in FIG. 5 ) on the opposite side of the magazine well 46 (shown in FIG. 5 ) from the barrel 22 , if an empty magazine (not shown) is held in the magazine well 46 (shown in FIG. 5 ). If a cartridge (shown in FIG. 7 ) is held in the magazine (not shown), the bolt 124 will push a cartridge out of the magazine and into the chamber 122 .
  • the firearm 10 of FIG. 1 is then ready to be fired.
  • the bolt 124 guides a firing pin 154 to properly strike a cartridge (shown in FIG. 7 ) causing it to fire.
  • the bolt carrier 126 includes a safety extension 156 .
  • the safety extension 156 is disposed beneath the firing pin 154 , so that the safety extension 156 is positioned between the firing pin 154 and the hammer 108 (shown in FIG. 5 ).
  • the safety extension extends within the pocket 103 of FIG. 5 .
  • the pocket 103 in conjunction with the safety extension 156 provides an additional measure of travel for the bolt carrier 124 within the upper receiver 14 .
  • Providing an additional measure of travel reduces the felt recoil of firing the firearm 10 by increasing the distance over which the recoil spring assembly 130 may absorb kinetic energy from the bolt 124 , bolt carrier 126 , and the operating rod 128 .
  • the safety extension 156 is positioned over the pin 112 (shown in FIG. 5 ), which prevents the hammer from pivoting far enough to strike the firing pin 154 .
  • the end 158 of the safety extension 156 is positioned past the pin 112 (shown in FIG. 5 ), allowing the hammer 108 to pivot far enough so that the head 114 of the hammer 108 (shown in FIG. 5 ) is able to strike the butt 160 of the firing pin 154 .
  • the neck 116 of the hammer 108 (shown in FIG.
  • the bolt 124 does not extend near the end 158 of the safety extension 156 until the bolt 124 has rotated within the bolt carrier 156 , because of the design of the bolt carrier 126 .
  • the barrel 22 is attached to the upper receiver 14 of FIG. 1 by a beveled barrel retention recess 162 and a barrel attachment device 164 .
  • the beveled barrel retention recess 162 may be disposed in the barrel extension 136 of the barrel 22 .
  • the beveled barrel retention recess 162 is beveled at an angle 166 .
  • the angle 166 may range from about 170 degrees to about 10 degrees. In some configurations, the angle 166 may range from about 120 degrees to about 40 degrees. Alternatively, the angle 166 may range from about 90 degrees to about 60 degrees.
  • the barrel attachment device 164 includes a tapered end 168 .
  • the angle 170 of the tapered end 168 is about the reciprocal angle of the angle 166 of the beveled barrel retention recess 162 .
  • the angle 170 of the tapered end 168 is about 280 degrees.
  • the barrel attachment device 164 may be connected to the upper receiver 14 of FIG. 4 via the barrel retention feature 86 .
  • the barrel attachment device 164 may also include a threaded section 172 so that the barrel attachment device 164 may be screwed into the barrel retention feature 86 by engaging the threads 88 of the barrel retention feature 86 .
  • the barrel 22 may be slid into the first passageway 60 of the upper receiver 14 shown in FIG. 4 with an end of the barrel 22 nearest to the chamber 122 .
  • the beveled barrel retention recess 162 of the barrel 22 is generally aligned with the tapered end 168 of the barrel attachment device 164 .
  • the tapered end 168 engages the beveled barrel retention recess 162 to attach the barrel 22 to the upper receiver 14 .
  • the angle 166 of the beveled barrel retention recess 162 facilitates the attachment of the barrel 22 to the upper receiver 14 of FIG. 4 because the angled surfaces of the tapered end 168 and the beveled barrel retention recess 162 encourages the barrel 22 to be attached at the same location each time the barrel 22 is attached to the upper receiver 14 .
  • the tapered end 168 engages the beveled barrel retention recess 162
  • the surfaces of the tapered end 168 and the beveled barrel retention recess 162 slide past each other until approximately 360 contact exists between the tapered end 168 and the beveled barrel retention recess 162 .
  • This attachment of the barrel 22 with increased repeatability at the same location of the receiver 14 of FIG. 4 minimizes variances in the “zero” of the firearm, as the barrel is removed and reattached.
  • “Zero” refers to the ability of a sighting device mounted on the firearm to predict the location of impact of a bullet fired from the firearm.
  • an exploded perspective view illustrates the bolt 124 of FIG. 6 .
  • the bolt 124 includes a protrusion 180 extending from the bolt 124 , three lugs 182 , an extractor slot 184 , a sliding extractor 186 , a detent 188 , a polymer spring 190 , a spring recess 192 , and a bolt face 194 .
  • the protrusion 180 includes an extraction surface 196 and a cam surface 198 .
  • the protrusion interacts with the bolt carrier 126 of FIG. 7 to rotate the bolt to lock and unlock the bolt against the chamber 122 (shown in FIG. 7 ).
  • the protrusion also interacts with the operating rod 128 of FIG. 7 to prevent the separation of the bolt 124 from the bolt carrier 126 .
  • the lugs 182 are used to lock the bolt 124 within the barrel extension 136 (shown in FIG. 6 ).
  • the lugs 182 also include a trip surface 200 that is used to initially cause the rotation of the bolt 124 into locking against the chamber 122 (shown in FIG. 6 ).
  • a second trip surface 201 is used to initially cause the rotation of the bolt 124 into unlocking the bolt 124 from against the chamber 122 . Because the first and second trip surfaces 200 and 201 are part of the lugs 182 , the bolt head is circular and has regular diameter centered on the bolt face 194 . This helps to evenly distribute the load forces among the lugs 182 .
  • the polymer spring 190 When the bolt 124 is assembled, the polymer spring 190 is seated within the spring recess 192 and the detent 188 extends from the spring recess 192 to retain the sliding extractor 186 within the extractor slot 184 .
  • the extractor 186 includes a surface (not shown) that mates with the detent 188 that allows the detent to convey the force of the polymer spring 190 to the extractor 186 .
  • the base 204 of the cartridge 202 abuts the bolt face 194 , which moves the extractor 186 away from a bottom surface 206 of the extractor slot 184 .
  • the movement of the extractor 186 forces the detent 188 into the spring recess 192 .
  • the polymer spring 190 is compressed within the spring recess 192 and applies an opposite force on the detent 188 that biases the extractor 186 against the base 204 of the cartridge 202 to retain the base 204 of the cartridge 202 against the bolt face 194 .
  • the extractor 186 moves toward the bottom surface 206 of the extractor slot 184 reducing the forces exerted on and by the polymer spring 190 .
  • the extractor 186 and the extractor slot 184 have a T-shape to better support the extractor 186 in order to avoid mechanical failure of the extractor.
  • the wings 208 of the top of the T-shape provide solid sections of extractor 186 to support the forces of extracting the cartridge 202 from the chamber 122 (shown in FIG. 6 ) and supporting the higher forces during firing of the firearm 10 .
  • the use of the sliding extractor 186 with a polymer spring 190 that permits the extractor 186 to support forces where rotating extractors (not shown) typically fail, because of the introduced weakness from using a pivot pin (not shown).
  • Weaknesses include a relatively large hole (not shown) extending through the extractor to accommodate the pivot pin (not shown), a large hole (not shown) extending through the lug used to accommodate the spring, and a thin lug structure (not shown) surrounding the rotating extractor (not shown).
  • the extractor 186 overcomes the weaknesses of a rotating extractor (not shown) by being stronger and smaller than a comparative rotating extractor (not shown). Additionally, the extractor 186 also includes an extractor head 210 that is supported by the barrel extension 136 shown in FIG. 6 to further prevent mechanical failure of the extractor 186 .
  • the polymer spring 190 may be a solid piece of polymer such as polyethylene, polypropylene, polyurethane, rubber, isoprene rubber, polybutadiene, neoprene, or any other polymer known in the art.
  • the polymer spring 190 is much smaller than an ordinary metal spring that may be used to support an extractor so that the hole in the lug 182 is much smaller than a hole for a metal spring. Therefore, the lug 182 supporting the extractor 186 is comparable to the other lugs 182 in strength.
  • FIG. 8 a cross section view along Section 8 - 8 of FIG. 6 of the bolt 124 engaging the barrel extension 136 before the bolt 124 has begun rotating to lock against the chamber 122 shown in FIG. 6 .
  • the bolt 124 include a plane 220 extending through the middle of the bolt face 194 and perpendicular to the bolt face 194 , an ejector access groove 222 , and the lugs 182 include a feed lug 224 , an extractor lug 226 , and a third lug 228 .
  • the ejector access groove permits the ejector 94 (shown in FIG. 4 ) to strike and eject a cartridge (shown in FIG. 7 ) from the firearm 10 that has been extracted from the chamber 122 (shown in FIG. 6 ).
  • the feed lug 224 is the lug used to push a cartridge (not shown) out of a magazine (not shown) and into the chamber 122 (shown in FIG. 6 ).
  • the extractor lug 226 supports the extractor 186 .
  • the third lug 228 provides an additional measure of support to the bolt 124 as it is locked within the barrel extension 136 .
  • the extractor 186 may be disposed at an angle 230 of less than about forty-five degrees but greater than about ten degrees from the plane 220 . In some configurations, the extractor 186 may be disposed at an angle 230 of about fifteen degrees to about thirty degrees. In other configurations, the extractor 186 may be disposed at an angle 230 of about twenty degrees to about twenty-five degrees.
  • the bolt 124 also includes guide surfaces 232 that are supported on the guidance feature 66 of the upper receiver 14 shown in FIG. 2 .
  • the guide surfaces 232 prevent the bolt 124 from rotating as the bolt 124 travels through the upper receiver 14 shown in FIG. 1 .
  • the barrel extension 136 includes locking features 234 that abut the lugs 182 to lock the bolt 124 within the barrel extension 136 .
  • the barrel extension 136 also includes an extractor cam surface 236 that interacts with the bolt head 210 to support the extractor 186 .
  • FIG. 9 a cross section view along Section 8 - 8 illustrates FIG. 6 of the bolt 124 locked within the barrel extension 136 .
  • the bolt 124 has rotated counter-clockwise to lock against the chamber 122 shown in FIG. 6 as viewed from the bolt 124 to the barrel 22 .
  • the locking features 234 abut the lugs 182 preventing the bolt 124 from separating from the barrel extension 136 and opening the chamber 122 (shown in FIG. 6 ).
  • the extractor head 210 of the extractor 186 has engaged the extractor cam surface 236 to reinforce the extractor 186 in clamping down on a base of a cartridge (shown in FIG. 7 ).
  • Using the barrel extension 136 to reinforce the extractor 186 helps to prevent damage to the bolt 124 and firearm 10 resulting from firing the firearm while there is blockage of the barrel 22 by reinforcing a normally weak part of the bolt 124 .
  • FIG. 10 a perspective view illustrates the bolt carrier 126 of FIG. 6 .
  • the bolt carrier 126 includes an operating rod slot 240 , a cam slot 242 , a forward assist feature 244 , and a charging handle feature 246 .
  • the operating rod slot 240 includes an opening 248 at an end of the bolt carrier 126 and a securing slot 250 .
  • the foot 144 of the operating rod 128 (shown in FIG. 6 ) engages the operating rod slot 240 to connect the operating rod 128 to the bolt carrier 126 .
  • the foot 144 of the operating rod 128 extends into the opening 248 at an end of the bolt carrier 126 once the bolt 124 (shown in FIG.
  • the foot 144 prevents the bolt 124 (shown in FIG. 7 ) from being separated from the bolt carrier 126 , while the operating rod 128 (shown in FIG. 6 ) is coupled with the bolt carrier 126 .
  • the foot 144 of the operating rod 128 (shown in FIG. 6 ) also extends into the securing slot 250 .
  • the cam slot 242 includes a locking guide 252 and support surface 254 .
  • the locking guide 252 assists the bolt 124 (shown in FIG. 7 ) by converting the linear motion of the bolt carrier 126 to rotational motion of the bolt 124 as the bolt carrier 126 is moved to abut the barrel extension 136 (shown in FIG. 6 ). This occurs as the bolt 124 (shown in FIG. 7 ) is disposed within the barrel extension 136 and abuts the chamber 122 (shown in FIG. 6 ), the bolt carrier 126 continues to move toward the barrel extension 136 so that the protrusion 180 of the bolt 124 slides within the locking guide 252 of the cam slot 242 .
  • the support surface 254 engages the cam surface 198 of the protrusion 180 (shown in FIG. 6 ).
  • the flat surface portions of the support surface 254 and the cam surface 198 of the protrusion 180 allow the bolt carrier 126 to guide the bolt 124 through the upper receiver 14 , without encouraging rotation of the bolt 124 .
  • the forward assist feature 244 and the charging handle feature 246 allow a user to use a charging handle (shown in FIG. 14 ) to manually move the bolt carrier 126 toward the chamber 122 or away from the chamber 122 shown in FIG. 6 by abutting the forward assist feature 244 or the charging handle feature 246 , respectively.
  • an alternative perspective view illustrates the bolt carrier 126 .
  • the bolt carrier 126 further includes carrier guide surfaces 256 .
  • the carrier guide surfaces 256 abut the guidance features 66 of the upper receiver 14 of FIG. 4 .
  • the safety extension 156 also includes an auto trip 258 that engages the auto sear 110 (shown in FIG. 5 ) to allow for automatic fire.
  • the auto trip 258 is disposed proximate the bottom of the bolt carrier 126 and is a surface of the safety extension 156 that engages the auto sear 110 (shown in FIG. 5 ) as the bolt carrier 126 abuts the chamber 122 (shown in FIG. 6 ).
  • the auto sear 110 may be disposed adjacent the hammer 108 as shown in FIG. 5 .
  • the bolt carrier 126 also includes an ejector slot 259 .
  • the ejector slot 259 provides the ejector 94 shown in FIG. 4 with the ability to extend into the bolt carrier 126 to eject a cartridge 202 (shown in FIG. 7 ) from the bolt face 194 via the ejector access groove 222 of the bolt 124 as shown in FIG. 8 .
  • a cross section view illustrates the operating rod 128 of FIG. 6 as having an anti-bounce mechanism 260 .
  • the anti-bounce mechanism 260 includes a plurality of weights 262 that are disposed within a chamber 264 of the piston 140 of the operating rod. Of course, a single weight 262 may be used.
  • the anti-bounce mechanism 260 by allowing the weights 262 to come to rest after the operating rod 128 , the bolt 124 , and bolt carrier 126 (shown in FIG. 6 ) have been stopped by the barrel 22 (shown in FIG. 6 ).
  • the abrupt stop of the operating rod 128 , the bolt 124 , and bolt carrier 126 (shown in FIG. 6 ) often results in reaction forces that may move the bolt 124 enough from the chamber 122 to cause a malfunction.
  • the delayed impact of the weights 262 counters the reaction forces by transferring the momentum of the weights 262 to the operating rod 128 , the bolt 124 , and bolt carrier 126 (shown in FIG. 6 ). Therefore, the anti-bounce mechanism 260 helps to keep the bolt carrier 126 properly positioned against the chamber 122 (shown in FIG. 6 ) to prevent possible malfunctions that may result from bolt carrier bounce.
  • the foot 144 of the operating rod 128 includes a front post 266 and a rear post 268 .
  • the front post 266 is disposed within the opening 248 of the bolt carrier 126 (shown in FIG. 10 ). While the front post 266 is disposed within the opening 248 of the bolt carrier 126 (shown in FIG. 10 ), the front post 266 prevents the protrusion 180 of FIG. 7 from leaving the cam slot 242 .
  • the rear post 268 is disposed within the securing slot 250 of the bolt carrier 126 (shown in FIG. 10 ).
  • a side elevation view illustrates the recoil spring assembly 130 of FIG. 6 .
  • the recoil spring assembly 130 includes a mating attachment structure 270 and a disassembly button 272 .
  • the mating attachment structure 270 engages with the attachment structure 102 of the lower receiver 16 (shown in FIG. 5 ) to attach the lower receiver 16 to the upper receiver 14 (shown in FIG. 1 ).
  • the mating attachment structure 270 is a protrusion that extends from an end of the recoil spring assembly 130 .
  • the mating attachment structure 270 may be a collar that fits around the protrusion.
  • Actuating the disassembly button 272 of the assembled firearm shown in FIG. 1 detaches the mating attachment structure 270 from the attachment structure 102 (shown in FIG. 5 ) to detach the lower receiver 16 from the upper receiver 14 of FIG. 1 .
  • the disassembly button 272 includes a neck 274 that extends into the disassembly button attachment point 74 as shown in FIGS. 3 and 4 so that the disassembly button 272 is disposed on the lateral 76 side of the upper receiver 14 .
  • the placement of the disassembly button 272 on the lateral 76 side of the upper receiver 14 allows the accessory rail at the 12 o'clock position 67 to extend the complete length of the upper receiver 14 as shown in FIG. 4 .
  • a side elevation view illustrates a non-reciprocating charging handle 280 with forward assist capability.
  • the charging handle 280 includes a body 282 having a groove 284 that engages the charging handle slot 71 (shown in FIG. 3 ).
  • the charging handle 280 further includes an engagement pin 286 , a handle 288 , and a detent 290 .
  • the charging handle 280 is retained in position on the firearm until desired by a user via the detent 290 .
  • the engagement pin 286 extends into the upper receiver through the charging handle access groove 99 .
  • the engagement pin 286 further includes a retaining ridge 292 that helps to prevent the engagement pin 286 from rotating in the upper receiver 14 .
  • the retaining ridge 292 is biased against the receiver 14 by a spring (not shown). In the biased position of the retaining ridge 292 , the engagement pin 286 extends into the upper receiver far enough to abut the charging handle feature 246 of the bolt carrier 126 shown in FIG. 10 .
  • the user pushes the handle 288 in the direction of the retaining ridge 292 .
  • a method may be used to change the caliber of the firearm 10 , described above, using caliber conversion parts.
  • the caliber conversion parts include a barrel designed for the desired cartridge in addition to barrel already attached to the firearm 10 , which is known in the art, and a bolt designed for the desired cartridge in addition to bolt already connected to the firearm 10 , which is also known in the art.
  • the caliber conversion parts are referred to in the method as a “second” barrel or a “second” bolt, even though the second barrel and second bolt are almost identical to the barrel 22 and bolt 124 shown in FIG. 6 , except for the small changes of dimensions inherent with changes in cartridge type that are well known by those of skill in the art.
  • a second barrel is needed to change the caliber of the firearm 10 .
  • Whether a second barrel or a second bolt is needed to change the caliber of the firearm 10 depends on how similar the dimensions of the first cartridge type to the second cartridge type, which information is known to those skilled in the art.
  • the method includes the steps of removing the barrel from the upper receiver, attaching the second barrel to the upper receiver, detaching the ejection buffer from the upper receiver at a first location, and attaching the ejection buffer to the upper receiver at a second location.
  • the method may include the further steps of removing the bolt, bolt carrier, and operating rod from the firearm, disconnecting the operating rod from the bolt carrier to allow removal of the bolt from the bolt carrier, removing the bolt from the bolt carrier, disposing the second bolt in the bolt carrier, connecting the operating rod to the bolt carrier to prevent removal of the second bolt from the bolt carrier, and disposing the second bolt, bolt carrier, and operating rod in the firearm.

Abstract

A firearm including a bolt for securing a barrel such that the barrel attaches to a receiver with increased repeatability at the same location. The bolt included a tapered end and may also include a threaded section. The receiver comprises a barrel attachment feature which allows the bolt to pass through and can also include threads for engaging the bolt. The barrel comprises a beveled recess for engaging the tapered end of the bolt. The angle of the tapered end and the beveled recess are approximately reciprocal. The bolt passes through the receiver and its tapered end engages the beveled recess to secure the barrel to the receiver.

Description

    RELATED APPLICATIONS
  • This utility application is a divisional of and claims priority to U.S. patent application Ser. No. 11/055,580 filed Feb. 10, 2005, entitled FIREARM, which claims the benefit of U.S. Provisional Application No. 60/544,586, filed Feb. 13, 2004, entitled IMPROVED FIREARM, and also claims the benefit of U.S. patent application Ser. No. 10/911,963, filed Aug. 4, 2004, entitled MULTI-CALIBER AMBIDEXTROUSLY CONTROLLABLE FIREARM, all of which are hereby incorporated herein by reference.
  • BACKGROUND OF THE INVENTION
  • The present invention relates to firearms. More specifically, the present invention relates to firearms that can be quickly configured with a minimum of additional parts to fire different calibers of ammunition with improved reliability in harsh environmental and firing conditions.
  • Currently available firearms have many limitations that can potentially place a user at risk, require long manufacturing times, or be expensive to produce. For example, receivers for firearms that include guidance features, such as internal rails, within a passageway tend to require significant effort to assemble. Often the rails are first manufactured and then attached to the receiver through welding or mechanical fasteners. Alternatively, the receiver is made in halves with integrally formed rails and then the halves are then welded together.
  • Currently available firearms also present serious safety issues where water is able to fill a barrel or a squib round is fired and the bullet fails to exit the barrel. In these situations, the pressures within the chamber may lead to mechanical failure of the firearm. Often the location of mechanical failure of the firearm is at or near the location of the extractor. A mechanical failure at or near the location of the extractor can render a firearm useless. In a combat situation, a useless firearm places the user at great risk.
  • Additionally, many currently available firearms that are used in combat and include a rotating bolt eject a spent cartridge upward into the air which may signal the location of the user of the firearm. Thus, the spent cartridge may give away the position of the user to an enemy during combat.
  • Some currently available firearms are able to fire different calibers of cartridges. However, these firearms all use the same size ejection port for each caliber, which may lead to problems with ejection. For example, the ejection port may be too large so that the spent cartridge is ejected in a random pattern. This random ejection pattern may lead to lost brass as well as user frustration as the brass may be ejected rearward into the user of the firearm. Where the ejection port is functional but slightly too small, the spent cartridge may fail to entirely eject from the firearm which may raise reliability issues.
  • Similarly, firearms that are able to fire different calibers of cartridges use the same ejector in the same location for all calibers, which can also lead to ejection problems with certain calibers or entirely prevent a firearm designed to fire one caliber from firing larger or smaller cartridges. For example, the ejector for a firearm designed to fire a 5.56 NATO cartridge may be unable to fire a Springfield 30.06 cartridge because the ejector is disposed too close to the barrel.
  • Currently available firearms for use with multiple calibers may also be difficult to take apart for cleaning or modification. Currently available firearms may also require relatively long periods of time to change from one caliber to another.
  • Accordingly, a need exists for a firearm that is reliable and durable under harsh conditions and is yet inexpensive to manufacture and requires a minimum of assembly. Furthermore, a need exists for a firearm that is able to reliably extract each round despite fouling and dirt in the receiver. Additionally, a need exists for a firearm that may be used reliably with a variety of differently sized cartridges. A need exists for a firearm that can withstand the pressures within the chamber that result from water or a bullet within the barrel without mechanical failure. A need also exists for a firearm that can eject a spent cartridge in a reliable manner laterally away from the user and not vertically in the air to give the user's position away. Accordingly, a need exists for a firearm that may be quickly changed from firing one caliber to another.
  • BRIEF SUMMARY OF THE INVENTION
  • The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available firearms. The firearm of the invention may be used to fire a cartridge that includes a base. The firearm generally includes a barrel having a chamber, a receiver, a bolt supported by the receiver; and a fire control group. The firearm may also include a firing pin. The fire control group may include a hammer, trigger, a bolt hold open device, a disconnect, an auto sear, and a fire selector/safety switch device. The firearm may also include a firing pin that is guided by the bolt.
  • In some embodiments, the receiver may be a two piece receiver that includes a lower receiver containing the fire control group and an integrally formed upper receiver that may include a longitudinal axis, a passageway extending generally parallel to the longitudinal axis, and a guidance feature extending into the passageway and along the passageway generally parallel to the longitudinal axis. The guidance feature may be an internal rail that guides the movement of the bolt within the upper receiver.
  • In some configurations, the upper receiver and its guidance feature and passageway are formed by extrusion. Additionally, the upper receiver may include a second passage way that is formed as the upper receiver is extruded. Extrusion permits the formation of multiple features in one processing step, which can minimize machining and assembly time and reduce manufacturing costs. For example, the upper receiver may be extruded with an accessory rail that extends parallel to the longitudinal axis. In some configurations, the accessory rail may be extruded at the 3, 6, 9, & 12 o'clock positions.
  • The upper receiver extrusion may be cut to size and then machined to provide additional features. For example, the integrally formed upper receiver may include a charging handle slot that is machined into the upper receiver and the extruded accessory rail may be machined to provide additional detail and utility to the accessory rail.
  • The barrel may be attached to the receiver or where a two piece receiver is used, the barrel may be attached to the upper receiver. The barrel may include a barrel extension with locking features for locking the bolt against the chamber. The barrel extension may also include a beveled barrel retention recess.
  • For attaching the barrel to the receiver, a barrel attachment device may be used. The barrel attachment device may have a threaded section and a tapered end. Additionally, the angle of the tapered end may be the reciprocal of the angle of the beveled barrel retention recess. The upper receiver may include a barrel retention feature that allows the barrel attachment device to be disposed in the barrel retention feature. The barrel retention feature may be threaded to allow the threaded section of the barrel attachment device to engage the barrel retention feature so that the tapered end engages the beveled barrel retention recess to attach the barrel to the upper receiver.
  • In some embodiments, the bolt may be connected to a bolt carrier. The bolt carrier may be supported by the upper receiver and may be guided by the guidance feature of the upper receiver. The bolt carrier may include an operating rod slot that is open at an end of the bolt carrier and a cam slot that extends from the operating rod slot. The bolt may include a protrusion that extends from the bolt and into the cam slot so that the protrusion is movable within the cam slot.
  • The bolt carrier may also include a safety extension disposed below the bolt. The safety extension of the bolt carrier prevents the hammer from striking the firing pin until the bolt is fully locked against the chamber. The safety extension may also include an auto trip. The auto trip engages the auto sear to allow for fully automatic fire of the firearm.
  • The bolt carrier may also include a forward assist feature that may be selectively engaged by a forward assist device of a non-reciprocating charging handle. The forward assist device of the charging handle is used to selectively engage the forward assist feature of the bolt carrier to provide manual locking of the bolt against the chamber.
  • The bolt may further include a bolt face and at least two lugs for locking the bolt face against the chamber of the barrel. In some configurations, the lugs of the bolt may be disposed within the barrel extension and abut the locking features of the barrel extension in order to close an end of the chamber with the bolt face allowing the firearm to be safely fired.
  • The bolt may also include an ejector access groove, a sliding extractor, and a polymer spring that biases the sliding extractor against the base of the cartridge to retain the base of the cartridge against the bolt face. The ejector access groove permits the bolt to move past an ejector so that the ejector may dislodge a cartridge from the bolt face. A polymer spring provides the advantage over metal springs that a polymer spring may be much smaller, and yet provide the same force as a larger metal spring. Therefore, a polymer spring permits smaller assemblies to be used that are not otherwise possible.
  • For convenience in describing some features of the bolt, the bolt includes a plane that extends through the middle of the bolt face and perpendicular to the bolt face. The sliding extractor may be disposed at an angle ranging from about thirty degrees to about fifteen degrees from the plane extending through the middle of the bolt face. Alternatively, the sliding extractor may be disposed at an angle ranging from about twenty-five degrees to about twenty degrees from the plane extending through the middle of the bolt face. This positioning of the sliding extractor and the ejector allows a spent cartridge to be ejected almost horizontally from the firearm, which minimizes the ability of an enemy to see the ejecting spent cartridges and pinpoint the location of the user of the firearm.
  • Where the barrel includes a barrel extension that includes a support surface, the extractor further includes an extractor head. As the bolt is locked within the barrel extension, the extractor head engages the support surface to support the extractor against the base of a cartridge. Having the support surface directly support the extractor helps to prevent mechanical failure of the extractor where abnormally high pressure occurs in the chamber during the firing of a cartridge.
  • The bolt may be rotated in a direction along the shortest distance from the feed lug to the extractor about the bolt face to lock the bolt face against the chamber or in other words, to close the chamber and allow the firearm to be safely discharge the cartridge. In some configurations of the invention, the bolt may also be rotated counter-clockwise to lock against the chamber as viewed from the bolt to the barrel.
  • The direction of bolt rotation can affect the angle of ejection of spent cartridges from the firearm, as well as the size and placement of lugs, extractor, and other features of the bolt. For example, in one embodiment of the invention, the counter-clockwise rotation of the bolt allows the use of three large lugs and a large extractor disposed at approximately 20 degrees from the plane about the bolt face.
  • The protrusion may be connected to the bolt carrier by an operating rod. Specifically, the operating rod may include a piston and a foot. The foot of the operating rod is disposable within the operating rod slot of the bolt carrier to prevent the bolt from separating from the bolt carrier and to connect the operating rod to the bolt carrier. More specifically, the foot of the operating rod is seated within the operating rod slot of the bolt carrier, which prevents the protrusion of the bolt from sliding out of the cam slot of the bolt carrier. Thus, the bolt is slidably connected to the bolt carrier.
  • The operating rod may further include an anti-bounce mechanism. As the bolt in some firearms is closed against the chamber, the force is great enough that the bolt carrier bounces so that the firearm may not function reliably. The anti-bounce mechanism counteracts this tendency to bounce.
  • Disposing the anti-bounce mechanism in the operating rod allows a smaller bolt carrier and bolt to be used in the firearm, which can result in a lighter and smaller firearm. In some embodiments of the invention, the anti-bounce mechanism of the operating rod includes a cavity disposed within the operating rod and one or more weights movable within the cavity. Specifically, once the bolt closes on the chamber, the weight moves within the cavity to be stopped at a end of the cavity. The transfer of energy from the weight to the operating rod and consequently to the bolt and the bolt carrier counteracts the bounce to keep the bolt carrier properly positioned against the chamber.
  • Where a two part receiver is used, the fire control group may be connected to the lower receiver of the firearm. The lower receiver may also include an attachment structure. The attachment structure is used to attach the lower receiver to the upper receiver.
  • The firearm may also include a recoil spring assembly disposed proximate the operating rod. In some configurations, the recoil spring assembly may be alternatively connected to the operating rod, the bolt carrier, the bolt, or the piston. The recoil spring assembly may include a mating attachment structure and a disassembly button. The mating attachment structure is attached to the attachment structure of the lower receiver to attach the lower receiver to the upper receiver. The disassembly button may be actuated to detach the mating attachment structure from the attachment structure in order to detach the lower receiver from the upper receiver. The disassembly button may be disposed on a lateral side of the upper receiver so that the upper receiver may include an accessory rail that extends the complete length of the upper receiver.
  • In some configurations, the ejector of the firearm may be attachable to the receiver at a plurality of locations. Having an ejector that is removably attachable to the receiver at a plurality of locations permits the firearm to accommodate different cartridge sizes. Specifically, adjusting the position of the ejector affects how a spent cartridge is ejected from the firearm.
  • The firearm in some configurations may also include an ejection buffer attachable to the receiver at a plurality of locations. The ejection buffer may be used to adjust the size of the ejection port of the firearm which also helps to permit the firearm to accommodate different cartridge sizes. For example, if the ejection port is too large, the spent cartridge may eject rearward toward the user of the firearm. If the ejection port is too small, the spent cartridge will fail to discharge, causing the firearm to fail.
  • The invention also includes a method for manufacturing an integrally formed upper receiver. The method includes the steps of extruding an upper receiver having a passageway and a guidance feature disposed in the passageway, and machining the upper receiver to form a barrel attachment feature. Alternatively, the guidance feature may be a slot that extends out of the passageway, such as a slot or groove. During the step of extruding the upper receiver, the upper receiver may also be extruded to include an accessory rail and a second passageway that is a gas tube hole.
  • The method may also include the steps of machining the accessory rail to provide grooves that extend perpendicular to the length of the accessory rail and machining a charging handle slot and a charging handle access groove into the upper receiver. Additionally, the method may include the step of machining the passageway and the second passage way to form a bolt carrier cavity.
  • Additionally, the invention includes a method for changing the caliber of a firearm with caliber conversion parts. The firearm includes at least a receiver, a barrel attached to the receiver, and an ejection buffer that is attachable to the upper receiver at a plurality of locations. The caliber conversion parts include at least a second barrel. The method includes the steps of removing the barrel from the upper receiver, attaching the second barrel to the upper receiver, detaching the ejection buffer from the upper receiver at a first location, and attaching the ejection buffer to the upper receiver at a second location.
  • Where the firearm further includes a bolt connected to a bolt carrier, an operating rod connected to the bolt carrier, wherein the bolt, bolt carrier, and operating rod are disposed within the firearm and the caliber conversion parts include a second bolt, the method may also include the steps of removing the bolt, bolt carrier, and operating rod from the firearm, disconnecting the operating rod from the bolt carrier to allow removal of the bolt from the bolt carrier, removing the bolt from the bolt carrier, disposing the second bolt in the bolt carrier, connecting the operating rod to the bolt carrier to prevent removal of the second bolt from the bolt carrier, and disposing the second bolt, bolt carrier, and operating rod in the firearm.
  • In addition to the components described above, the firearm may include furniture such as a hand guard, a butt stock, and a pistol grip. The hand guard may be attached to the firearm proximate the barrel. The butt stock and pistol grip may be attached to the receiver or in some configurations, the lower receiver. The firearm may also include a feed attachment device such as a magazine well or belt feed mechanism.
  • These and other features of the present invention will become more fully apparent from the following description, or may be learned by the practice of the invention as set forth hereinafter.
  • BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
  • In order that the manner in which the above-recited and other features and advantages of the invention are obtained will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
  • FIG. 1 is a side elevation view of a firearm according to the invention;
  • FIG. 2 is a rear elevation view of the upper receiver of the firearm as extruded;
  • FIG. 3 is a rear elevation view of the finished upper receiver of FIG. 2;
  • FIG. 4 is a perspective view of a cross section taken along Section 3-3 of the
  • FIG. 5 is a perspective view of the lower receiver containing components of the fire control group;
  • FIG. 6 is an exploded side elevation view of the operating system of the firearm;
  • FIG. 7 is an exploded perspective view of a bolt of firearm;
  • FIG. 8 is a cross section view along Section 8-8 of FIG. 6 of the bolt engaging a barrel extension of the firearm;
  • FIG. 9 is a cross section view along Section 8-8 of FIG. 6 of the bolt locked within the barrel extension;
  • FIG. 10 is a perspective view of a bolt carrier according to the invention;
  • FIG. 11 is an alternative perspective view of a bolt carrier according to the invention;
  • FIG. 12 is a cross section view of the operating rod of FIG. 6 that includes an anti-bounce mechanism;
  • FIG. 13 is a side elevation view of a recoil spring assembly; and
  • FIG. 14 is a side elevation view of a non-reciprocating charging handle with forward assist capability.
  • DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
  • The presently preferred embodiments of the present invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. It will be readily understood that the components of the present invention, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the improved firearm of the present invention, as represented in FIGS. 1 through 14, is not intended to limit the scope of the invention, as claimed, but is merely representative of presently preferred embodiments of the invention.
  • For this application, the phrases “connected to,” “coupled to,” and “in communication with” refer to any form of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, and thermal interaction. The phrase “attached to” refers to a form of mechanical coupling that restricts relative translation or rotation between the attached objects.
  • The term “abutting” refers to items that are in direct physical contact with each other, although the items may not be attached together. The terms “integrally formed” refer to a body that is manufactured integrally, i.e., as a single piece, without requiring the assembly of multiple pieces. Multiple parts may be integrally formed with each other if they are formed from a single work piece. Thus, parts that are welded or otherwise fastened together are not integrally formed.
  • Referring to FIG. 1, a side elevation view illustrates a firearm 10 according to the invention. As shown, the firearm 10 includes a receiver 12 that includes an upper receiver 14 and a lower receiver 16. The upper receiver 14 may be integrally formed with accessory rails 18 and an ejection port 20 for allowing spent cartridges (not shown) from the firearm 10.
  • The firearm 10 also includes a barrel 22 that is attached to the upper receiver 14. Optionally, the firearm 10 may also include a front sight 24, a rear sight 26, hand guards 28, and a flash hider 30. In some configurations, the firearm 10 may include vertical grips, a grenade launcher, a bayonet lug, a muzzle brake, a scope, a red dot sight, a rangefinder, a silencer, a light system, a laser, or other accessories known in the art. The hand guards 28 are shown attached to the integral accessory rail system 18 and may be removed as desired by a user.
  • The lower receiver 16 may be attached to a butt stock 32 and a pistol grip 34. A fire control group 36 including a trigger 38, a selector/safety switch 40, and a bolt hold open device 44 are coupled to the lower receiver 16 in this configuration. In some configurations, the fire control group may be coupled to the receiver 12 or the upper receiver 14. The lower receiver 16 may be integrally formed with a magazine well 46 for receiving a magazine (not shown). Alternatively, the magazine well, cartridge feeding device, or a belt feed device (not shown) may be separately formed and connected to the firearm.
  • The upper receiver 14 and the lower receiver 16 are pivotally coupled by a receiver pin 50. The receiver pin 50 allows the upper receiver 14 to be pivoted away from the lower receiver 16 providing access to internal components for cleaning and maintenance.
  • The firearm 10 also includes an ejection buffer 52 attachable to the upper receiver 14 at a plurality of locations. The ejection buffer 52 is used to adjust the size of the ejection port as well as to better control the direction of ejection of spent cartridges. More specifically, the ejection buffer may be attached at a first location 54 or at a second location 56 or at any location in between the first location 54 and the second location 56, depending on the caliber of cartridge that a user desires to fire from the firearm 10. For example, the first location 54 may be used for calibers with smaller cartridges and the second location 56 may be used for larger cartridges.
  • Referring to FIG. 2, a rear elevation view illustrates the upper receiver 14 of the firearm 10 of FIG. 10. The upper receiver 14 may be initially formed by extrusion and may be made of aluminum or steel. Alternatively, the upper receiver 14 may be made of any plastic, composite, ceramic, or metal that is relatively tough and wear resistant. Extruding the upper receiver 14 permits several features of the upper receiver 14 to be formed at the time of extrusion, which lowers manufacturing costs and production time. Additionally, extruding the upper receiver 14 provides the upper receiver 14 with a natural longitudinal is so that the features formed during extrusion extend generally parallel to the longitudinal axis.
  • As shown, the upper receiver 14 is extruded to include the accessory rails 18, a first passageway 60, a second passageway 62, and guidance features 64. The guidance features 64 extend into the passageway and along the passageway to help guide a bolt (shown in FIG. 6) or a bolt carrier (shown in FIG. 6) through the first passageway 60 of the receiver 12. The guidance features 64 as shown include internal rails 65 and shoulders 66 that are used to guide the movement of internal components of the firearm 10. The accessory rails 18 include a rail at the 12 o'clock position 67, the 3 o'clock position 68, the 6 o'clock position 69, and the 9 o'clock position 70.
  • An advantage of extruding the features of the upper receiver 14 is that the features formed by extrusion are generally straight and parallel to each other. Otherwise assembly may result in a great deal of variation.
  • Referring to FIG. 3, a rear elevation view shows the finished upper receiver 14 of FIG. 2. Once the upper receiver 14 is extruded, various machining methods known in the art, such as drilling, tapping, milling, etc., are used to form other integral features of the upper receiver 14. As shown, the upper receiver 14 when finished may include a charging handle slot 71, a operating rod cavity 72, a disassembly button attachment point 74, and other features known in the art that enhance the functional and aesthetic qualities of the upper receiver 14.
  • The upper receiver 14 also has a lateral direction 76 and a vertical direction 78. The disassembly button attachment point 74 disposes a disassembly button (shown in FIG. 13) on a lateral 76 side of the upper receiver 14. The disassembly button (shown in FIG. 13) permits the upper receiver 14 to be selectively detached and attached to the lower receiver 16 shown in FIG. 1. By disposing the disassembly button attachment point 74 on the lateral 76 side of the upper receiver 14 a user may grip the upper receiver and slide the disassembly button (shown in FIG. 13) to detach the upper receiver 14 from the lower receiver 16 of FIG. 1.
  • Additionally, the upper receiver 14 includes a bottom cut 79 that allows the fire control group 36 and other components of the lower receiver 16 to interact with the components connected to the upper receiver 14.
  • Referring to FIG. 4, a perspective view of a cross section taken along Section 3-3 illustrates the finished upper receiver 14 of FIG. 3. As shown, the first passageway 60, the second passageway 62, the guidance features 64 extend generally parallel to a longitudinal axis 80. The operating rod cavity 72 also extends generally parallel to the longitudinal axis 80 and midway into the upper receiver 14. The accessory rail 18 has been machined to provide grooves 82 that extend perpendicular to the longitudinal axis 80 so that the accessory rail 18 as shown is a 1913 type accessory rail.
  • Lightening cuts 84 have also been made in the upper receiver 14 in order to reduce the weight of the upper receiver 14. The upper receiver 14 also includes a barrel attachment feature 86 that may be a threaded hole 88. A pivot hole 90 has also been machined that allows the upper receiver 14 to pivot around the receiver pin 50 (shown in FIG. 1).
  • A plurality of holes 92 have also been cut to provide for the attachment of an ejector 94 to the upper receiver at a plurality of locations. More specifically, the ejector may be attached at a first location 96 or a second location 98. The first location 96 may be used for calibers with smaller cartridges and the second location 98 may be used for larger cartridges.
  • The upper receiver 14 also includes a charging handle access groove 99 that permits a charging handle (shown in FIG. 14) disposed in the charging handle slot 71 to access the interior of the upper receiver 14.
  • Referring to FIG. 5, a perspective view illustrates the lower receiver 16 containing components of the fire control group 36. The lower receiver 16 includes a pivot hole 100 that allows the lower receiver 16 to pivot around the receiver pin 50 (shown in FIG. 1). The lower receiver 16 also includes an attachment structure 102 for attaching the lower receiver 16 to the upper receiver 14 of FIG. 1. The lower receiver 16 includes a pocket 103 that will be described below in relation to FIG. 6. In this embodiment, the attachment structure 102 is a hole that engages a mating attachment structure (shown in FIG. 13) that is connected to the upper receiver 14 of FIG. 1.
  • The lower receiver 16 is shown integrally formed with a magazine well 46 for receiving a magazine (not shown). The magazine well 46 includes a magazine release 104 that operates a magazine catch 106 that retains the magazine (not shown) in the magazine well 46.
  • The lower receiver 16 may be made of plastic, metal, ceramic, or composite. Furthermore, the lower receiver 16 may be manufactured by injection molding, casting, machining, or any other manufacturing process known in the art.
  • The fire control group 36 includes a trigger 38, a selector/safety switch 40, and a bolt hold open device 44. The fire control group 36 also includes a hammer 108 and an auto sear 1 10. The hammer 108 is used to impart kinetic energy to a firing pin (shown in FIG. 6) when the trigger 38 is pulled or for fully automatic firing of the firearm 10 when the trigger 38 is pulled and the auto sear 110 is tripped.
  • As shown, the hammer 108 is in a set position that is ready to strike the firing pin (not shown). When the hammer 108 is released, the hammer 108 pivots about a pin 112 and a head 114 of the hammer 108 strikes an end of the firing pin (shown in FIG. 6). The hammer 108 also includes a neck 116 that increases the angular momentum of the head 116.
  • Referring to FIG. 6 is an exploded side elevation view of the operating system 120 of the firearm 10 of FIG. 1. The operating system 120 includes the barrel 22 having a chamber 122, a bolt 124, a bolt carrier 126, an operating rod 128, a recoil spring assembly 130, a gas tube 132. The barrel 22 may include a gas block 134, and a barrel extension 136 and is shown attached to the gas block 134 and the barrel extension 136. The barrel 22 may be attached to the gas block 134 and the barrel extension 136 by welding, pinning, brazing, threading, and other methods known in the art.
  • When a cartridge (shown in FIG. 7) is disposed within the chamber 122 and fired, a propellant disposed within the cartridge is burned to produce gas and increase the pressure within the chamber 122. The high pressure gas then pushes a bullet (not shown) out of the barrel 22 toward a target. The high pressure gas flows through the barrel 22 from the chamber 122 toward the gas block 134. Upon reaching the gas block 134, the high pressure gas exits the barrel 22 through a hole (not shown) in the barrel 22 and into the gas block 134.
  • The gas block 134 directs the gas into the gas tube 132. With reference to FIG. 2, the gas tube 132 is disposed within the second passageway 62 of the upper receiver 14. In some configurations, the second passageway 62 is the gas tube 132 and directly connected to the gas block 134.
  • The operating rod 128 includes a piston 140, a recoil tube 142, and a foot 144. The piston 140 is disposed within the gas tube 132 proximate the gas block 134. As the high pressure gas enters the gas tube, the high pressure gas pushes the piston 140 away from the gas block 134. The gas tube 132 includes vent holes 146 that help to prevent the high pressure gas from entering the operating rod cavity 72 of the upper receiver 14 (shown in FIG. 4). The high pressure gas is able then able to exit the firearm through the lightening cuts 84 (shown in FIG. 4) from the vent holes 146. Where the second passageway 62 is the gas tube 132, the gas vents directly through the lightening cuts 84 (shown in FIG. 4).
  • Preventing the high pressure gas from entering the operating rod cavity 72 of the upper receiver 14 (shown in FIG. 4) can be important because the high pressure gas deposits carbon, powder residue, and lead on the surfaces of the firearm 10 that the high pressure gas comes into contact with. These deposits can lead to firearm malfunctions, such as jamming, feeding problems, and ejection failures.
  • The recoil spring assembly 130 includes a spring 148 surrounding a guide rod 150 and a sliding rod 152. The recoil spring assembly 130 is connected to the operating rod 128 by being partially disposed within the recoil tube 142 of the operating rod 128. Alternatively, the recoil spring assembly 130 may be connected to the bolt carrier 126 or the bolt 124.
  • Thus, as the operating rod 128 moves away from the gas block 134 in reaction to the high pressure gas, the recoil spring assembly 130 is compressed and stores the kinetic energy of the moving operating rod 128 as potential energy in the spring 148 as the sliding rod 150 slides within the guide rod 150.
  • Additionally, the operating rod 128 is connected to the bolt carrier 126. The bolt carrier 126 carries the bolt 124 through the upper receiver 14 of FIG. 4 to lock or abut the bolt 124 against the chamber 122. Because the bolt carrier 126 is connected to the bolt 124, the bolt 124 moves as the bolt carrier 126 moves. Thus, as the operating rod 128 moves away from the gas block 134 in reaction to the high pressure gas, the bolt carrier 126 moves the bolt 124 to unlock from barrel extension 136 and from against the chamber 122.
  • As the bolt 124 moves away from the gas block 134, the bolt 124 removes the spent cartridge (shown in FIG. 7) from the chamber 122. As the bolt 124 moves away from the chamber 122, the bolt 124 moves past the ejector 94 of FIG. 4 so that the ejector 94 strikes the spent cartridge (shown in FIG. 7) to knock the spent cartridge from the bolt 124 and eject the spent cartridge through the ejection port 20 and out of the firearm 10 shown in FIG. 1. Additionally, the bolt 124 and bolt carrier 126 contact the head 114 of the hammer 108 (shown in FIG. 5) to place the hammer 108 in the set position as shown in FIG. 5.
  • Eventually, the operating rod 128, the bolt carrier 126, and the bolt 124 come to rest near an end of the upper receiver 14 of FIG. 4. Then, the recoil spring assembly 130 releases the potential energy stored in the spring 148 to push the operating rod 128, the bolt carrier 126, and the bolt 124 toward the gas block 134. As the bolt 124 moves toward the chamber 122, the bolt may be stopped by the bolt hold open device 44 (shown in FIG. 5) on the opposite side of the magazine well 46 (shown in FIG. 5) from the barrel 22, if an empty magazine (not shown) is held in the magazine well 46 (shown in FIG. 5). If a cartridge (shown in FIG. 7) is held in the magazine (not shown), the bolt 124 will push a cartridge out of the magazine and into the chamber 122. The firearm 10 of FIG. 1 is then ready to be fired.
  • The bolt 124 guides a firing pin 154 to properly strike a cartridge (shown in FIG. 7) causing it to fire. The bolt carrier 126 includes a safety extension 156. The safety extension 156 is disposed beneath the firing pin 154, so that the safety extension 156 is positioned between the firing pin 154 and the hammer 108 (shown in FIG. 5). When the bolt carrier 126 is furthest from the gas block 134, the safety extension extends within the pocket 103 of FIG. 5. The pocket 103 in conjunction with the safety extension 156 provides an additional measure of travel for the bolt carrier 124 within the upper receiver 14.
  • Providing an additional measure of travel reduces the felt recoil of firing the firearm 10 by increasing the distance over which the recoil spring assembly 130 may absorb kinetic energy from the bolt 124, bolt carrier 126, and the operating rod 128.
  • As the bolt 124 nears the chamber 122 but before the bolt 124 is locked against the chamber 122, the safety extension 156 is positioned over the pin 112 (shown in FIG. 5), which prevents the hammer from pivoting far enough to strike the firing pin 154. Once the bolt is locked against the chamber 122, the end 158 of the safety extension 156 is positioned past the pin 112 (shown in FIG. 5), allowing the hammer 108 to pivot far enough so that the head 114 of the hammer 108 (shown in FIG. 5) is able to strike the butt 160 of the firing pin 154. The neck 116 of the hammer 108 (shown in FIG. 5) may abut the end 158 of the safety extension 156 to place the head 114 of the hammer (shown in FIG. 5) above the safety extension 156. Additionally, the bolt 124 does not extend near the end 158 of the safety extension 156 until the bolt 124 has rotated within the bolt carrier 156, because of the design of the bolt carrier 126.
  • The barrel 22 is attached to the upper receiver 14 of FIG. 1 by a beveled barrel retention recess 162 and a barrel attachment device 164. In configurations where the barrel 22 includes a barrel extension 136, the beveled barrel retention recess 162 may be disposed in the barrel extension 136 of the barrel 22. The beveled barrel retention recess 162 is beveled at an angle 166. The angle 166 may range from about 170 degrees to about 10 degrees. In some configurations, the angle 166 may range from about 120 degrees to about 40 degrees. Alternatively, the angle 166 may range from about 90 degrees to about 60 degrees.
  • The barrel attachment device 164 includes a tapered end 168. The angle 170 of the tapered end 168 is about the reciprocal angle of the angle 166 of the beveled barrel retention recess 162. For example, if the angle 166 of the beveled barrel retention recess 162 is about 80 degrees, the angle 170 of the tapered end 168 is about 280 degrees.
  • The barrel attachment device 164 may be connected to the upper receiver 14 of FIG. 4 via the barrel retention feature 86. The barrel attachment device 164 may also include a threaded section 172 so that the barrel attachment device 164 may be screwed into the barrel retention feature 86 by engaging the threads 88 of the barrel retention feature 86. Once the barrel attachment device 164 is connected to the upper receiver 14, the barrel 22 may be slid into the first passageway 60 of the upper receiver 14 shown in FIG. 4 with an end of the barrel 22 nearest to the chamber 122. Next, the beveled barrel retention recess 162 of the barrel 22 is generally aligned with the tapered end 168 of the barrel attachment device 164. Next, the tapered end 168 engages the beveled barrel retention recess 162 to attach the barrel 22 to the upper receiver 14.
  • The angle 166 of the beveled barrel retention recess 162 facilitates the attachment of the barrel 22 to the upper receiver 14 of FIG. 4 because the angled surfaces of the tapered end 168 and the beveled barrel retention recess 162 encourages the barrel 22 to be attached at the same location each time the barrel 22 is attached to the upper receiver 14. As the tapered end 168 engages the beveled barrel retention recess 162, the surfaces of the tapered end 168 and the beveled barrel retention recess 162 slide past each other until approximately 360 contact exists between the tapered end 168 and the beveled barrel retention recess 162. This attachment of the barrel 22 with increased repeatability at the same location of the receiver 14 of FIG. 4 minimizes variances in the “zero” of the firearm, as the barrel is removed and reattached. “Zero” refers to the ability of a sighting device mounted on the firearm to predict the location of impact of a bullet fired from the firearm.
  • Referring to FIG. 7, an exploded perspective view illustrates the bolt 124 of FIG. 6. As shown, the bolt 124 includes a protrusion 180 extending from the bolt 124, three lugs 182, an extractor slot 184, a sliding extractor 186, a detent 188, a polymer spring 190, a spring recess 192, and a bolt face 194. The protrusion 180 includes an extraction surface 196 and a cam surface 198. The protrusion interacts with the bolt carrier 126 of FIG. 7 to rotate the bolt to lock and unlock the bolt against the chamber 122 (shown in FIG. 7). The protrusion also interacts with the operating rod 128 of FIG. 7 to prevent the separation of the bolt 124 from the bolt carrier 126.
  • The lugs 182 are used to lock the bolt 124 within the barrel extension 136 (shown in FIG. 6). The lugs 182 also include a trip surface 200 that is used to initially cause the rotation of the bolt 124 into locking against the chamber 122 (shown in FIG. 6). A second trip surface 201 is used to initially cause the rotation of the bolt 124 into unlocking the bolt 124 from against the chamber 122. Because the first and second trip surfaces 200 and 201 are part of the lugs 182, the bolt head is circular and has regular diameter centered on the bolt face 194. This helps to evenly distribute the load forces among the lugs 182.
  • When the bolt 124 is assembled, the polymer spring 190 is seated within the spring recess 192 and the detent 188 extends from the spring recess 192 to retain the sliding extractor 186 within the extractor slot 184. The extractor 186 includes a surface (not shown) that mates with the detent 188 that allows the detent to convey the force of the polymer spring 190 to the extractor 186.
  • When the bolt engages a cartridge 202, the base 204 of the cartridge 202 abuts the bolt face 194, which moves the extractor 186 away from a bottom surface 206 of the extractor slot 184. The movement of the extractor 186 forces the detent 188 into the spring recess 192. The polymer spring 190 is compressed within the spring recess 192 and applies an opposite force on the detent 188 that biases the extractor 186 against the base 204 of the cartridge 202 to retain the base 204 of the cartridge 202 against the bolt face 194. Once the cartridge 202 is removed from the bolt face 194, the extractor 186 moves toward the bottom surface 206 of the extractor slot 184 reducing the forces exerted on and by the polymer spring 190.
  • The extractor 186 and the extractor slot 184 have a T-shape to better support the extractor 186 in order to avoid mechanical failure of the extractor. The wings 208 of the top of the T-shape provide solid sections of extractor 186 to support the forces of extracting the cartridge 202 from the chamber 122 (shown in FIG. 6) and supporting the higher forces during firing of the firearm 10. The use of the sliding extractor 186 with a polymer spring 190 that permits the extractor 186 to support forces where rotating extractors (not shown) typically fail, because of the introduced weakness from using a pivot pin (not shown). Weaknesses include a relatively large hole (not shown) extending through the extractor to accommodate the pivot pin (not shown), a large hole (not shown) extending through the lug used to accommodate the spring, and a thin lug structure (not shown) surrounding the rotating extractor (not shown).
  • The extractor 186 overcomes the weaknesses of a rotating extractor (not shown) by being stronger and smaller than a comparative rotating extractor (not shown). Additionally, the extractor 186 also includes an extractor head 210 that is supported by the barrel extension 136 shown in FIG. 6 to further prevent mechanical failure of the extractor 186.
  • The polymer spring 190 may be a solid piece of polymer such as polyethylene, polypropylene, polyurethane, rubber, isoprene rubber, polybutadiene, neoprene, or any other polymer known in the art. The polymer spring 190 is much smaller than an ordinary metal spring that may be used to support an extractor so that the hole in the lug 182 is much smaller than a hole for a metal spring. Therefore, the lug 182 supporting the extractor 186 is comparable to the other lugs 182 in strength.
  • Referring to FIG. 8, a cross section view along Section 8-8 of FIG. 6 of the bolt 124 engaging the barrel extension 136 before the bolt 124 has begun rotating to lock against the chamber 122 shown in FIG. 6. As shown, the bolt 124 include a plane 220 extending through the middle of the bolt face 194 and perpendicular to the bolt face 194, an ejector access groove 222, and the lugs 182 include a feed lug 224, an extractor lug 226, and a third lug 228.
  • The ejector access groove permits the ejector 94 (shown in FIG. 4) to strike and eject a cartridge (shown in FIG. 7) from the firearm 10 that has been extracted from the chamber 122 (shown in FIG. 6). The feed lug 224 is the lug used to push a cartridge (not shown) out of a magazine (not shown) and into the chamber 122 (shown in FIG. 6). The extractor lug 226 supports the extractor 186. The third lug 228 provides an additional measure of support to the bolt 124 as it is locked within the barrel extension 136.
  • The extractor 186 may be disposed at an angle 230 of less than about forty-five degrees but greater than about ten degrees from the plane 220. In some configurations, the extractor 186 may be disposed at an angle 230 of about fifteen degrees to about thirty degrees. In other configurations, the extractor 186 may be disposed at an angle 230 of about twenty degrees to about twenty-five degrees.
  • The bolt 124 also includes guide surfaces 232 that are supported on the guidance feature 66 of the upper receiver 14 shown in FIG. 2. The guide surfaces 232 prevent the bolt 124 from rotating as the bolt 124 travels through the upper receiver 14 shown in FIG. 1.
  • The barrel extension 136 includes locking features 234 that abut the lugs 182 to lock the bolt 124 within the barrel extension 136. The barrel extension 136 also includes an extractor cam surface 236 that interacts with the bolt head 210 to support the extractor 186.
  • Referring to FIG. 9, a cross section view along Section 8-8 illustrates FIG. 6 of the bolt 124 locked within the barrel extension 136. As shown, the bolt 124 has rotated counter-clockwise to lock against the chamber 122 shown in FIG. 6 as viewed from the bolt 124 to the barrel 22. The locking features 234 abut the lugs 182 preventing the bolt 124 from separating from the barrel extension 136 and opening the chamber 122 (shown in FIG. 6). The extractor head 210 of the extractor 186 has engaged the extractor cam surface 236 to reinforce the extractor 186 in clamping down on a base of a cartridge (shown in FIG. 7). Using the barrel extension 136 to reinforce the extractor 186 helps to prevent damage to the bolt 124 and firearm 10 resulting from firing the firearm while there is blockage of the barrel 22 by reinforcing a normally weak part of the bolt 124.
  • Referring to FIG. 10, a perspective view illustrates the bolt carrier 126 of FIG. 6. The bolt carrier 126 includes an operating rod slot 240, a cam slot 242, a forward assist feature 244, and a charging handle feature 246. The operating rod slot 240 includes an opening 248 at an end of the bolt carrier 126 and a securing slot 250. The foot 144 of the operating rod 128 (shown in FIG. 6) engages the operating rod slot 240 to connect the operating rod 128 to the bolt carrier 126. The foot 144 of the operating rod 128 (shown in FIG. 6) extends into the opening 248 at an end of the bolt carrier 126 once the bolt 124 (shown in FIG. 7) is coupled to the bolt carrier 126 and the protrusion 180 of the bolt 124 (shown in FIG. 7) is disposed within the cam slot 242. The foot 144 prevents the bolt 124 (shown in FIG. 7) from being separated from the bolt carrier 126, while the operating rod 128 (shown in FIG. 6) is coupled with the bolt carrier 126. The foot 144 of the operating rod 128 (shown in FIG. 6) also extends into the securing slot 250.
  • The cam slot 242 includes a locking guide 252 and support surface 254. The locking guide 252 assists the bolt 124 (shown in FIG. 7) by converting the linear motion of the bolt carrier 126 to rotational motion of the bolt 124 as the bolt carrier 126 is moved to abut the barrel extension 136 (shown in FIG. 6). This occurs as the bolt 124 (shown in FIG. 7) is disposed within the barrel extension 136 and abuts the chamber 122 (shown in FIG. 6), the bolt carrier 126 continues to move toward the barrel extension 136 so that the protrusion 180 of the bolt 124 slides within the locking guide 252 of the cam slot 242.
  • As the bolt 124 of FIG. 7 is moved toward the chamber 122 (shown in FIG. 6), the support surface 254 engages the cam surface 198 of the protrusion 180 (shown in FIG. 6). The flat surface portions of the support surface 254 and the cam surface 198 of the protrusion 180 (shown in FIG. 6) allow the bolt carrier 126 to guide the bolt 124 through the upper receiver 14, without encouraging rotation of the bolt 124.
  • The forward assist feature 244 and the charging handle feature 246 allow a user to use a charging handle (shown in FIG. 14) to manually move the bolt carrier 126 toward the chamber 122 or away from the chamber 122 shown in FIG. 6 by abutting the forward assist feature 244 or the charging handle feature 246, respectively.
  • Referring to FIG. 11, an alternative perspective view illustrates the bolt carrier 126. The bolt carrier 126 further includes carrier guide surfaces 256. The carrier guide surfaces 256 abut the guidance features 66 of the upper receiver 14 of FIG. 4. As shown, the safety extension 156 also includes an auto trip 258 that engages the auto sear 110 (shown in FIG. 5) to allow for automatic fire. The auto trip 258 is disposed proximate the bottom of the bolt carrier 126 and is a surface of the safety extension 156 that engages the auto sear 110 (shown in FIG. 5) as the bolt carrier 126 abuts the chamber 122 (shown in FIG. 6). By including the auto trip 258 as part of the safety extension 156, the auto sear 110 may be disposed adjacent the hammer 108 as shown in FIG. 5.
  • The bolt carrier 126 also includes an ejector slot 259. The ejector slot 259 provides the ejector 94 shown in FIG. 4 with the ability to extend into the bolt carrier 126 to eject a cartridge 202 (shown in FIG. 7) from the bolt face 194 via the ejector access groove 222 of the bolt 124 as shown in FIG. 8.
  • Referring to FIG. 12, a cross section view illustrates the operating rod 128 of FIG. 6 as having an anti-bounce mechanism 260. The anti-bounce mechanism 260 includes a plurality of weights 262 that are disposed within a chamber 264 of the piston 140 of the operating rod. Of course, a single weight 262 may be used.
  • The anti-bounce mechanism 260 by allowing the weights 262 to come to rest after the operating rod 128, the bolt 124, and bolt carrier 126 (shown in FIG. 6) have been stopped by the barrel 22 (shown in FIG. 6). The abrupt stop of the operating rod 128, the bolt 124, and bolt carrier 126 (shown in FIG. 6) often results in reaction forces that may move the bolt 124 enough from the chamber 122 to cause a malfunction. The delayed impact of the weights 262 counters the reaction forces by transferring the momentum of the weights 262 to the operating rod 128, the bolt 124, and bolt carrier 126 (shown in FIG. 6). Therefore, the anti-bounce mechanism 260 helps to keep the bolt carrier 126 properly positioned against the chamber 122 (shown in FIG. 6) to prevent possible malfunctions that may result from bolt carrier bounce.
  • The foot 144 of the operating rod 128 includes a front post 266 and a rear post 268. The front post 266 is disposed within the opening 248 of the bolt carrier 126 (shown in FIG. 10). While the front post 266 is disposed within the opening 248 of the bolt carrier 126 (shown in FIG. 10), the front post 266 prevents the protrusion 180 of FIG. 7 from leaving the cam slot 242. The rear post 268 is disposed within the securing slot 250 of the bolt carrier 126 (shown in FIG. 10).
  • Referring to FIG. 13, a side elevation view illustrates the recoil spring assembly 130 of FIG. 6. As shown, the recoil spring assembly 130 includes a mating attachment structure 270 and a disassembly button 272. The mating attachment structure 270 engages with the attachment structure 102 of the lower receiver 16 (shown in FIG. 5) to attach the lower receiver 16 to the upper receiver 14 (shown in FIG. 1). The mating attachment structure 270 is a protrusion that extends from an end of the recoil spring assembly 130. Alternatively, where the attachment structure 102 of the lower receiver 16 is a protrusion rather than a hole, the mating attachment structure 270 may be a collar that fits around the protrusion.
  • Actuating the disassembly button 272 of the assembled firearm shown in FIG. 1 detaches the mating attachment structure 270 from the attachment structure 102 (shown in FIG. 5) to detach the lower receiver 16 from the upper receiver 14 of FIG. 1. The disassembly button 272 includes a neck 274 that extends into the disassembly button attachment point 74 as shown in FIGS. 3 and 4 so that the disassembly button 272 is disposed on the lateral 76 side of the upper receiver 14. The placement of the disassembly button 272 on the lateral 76 side of the upper receiver 14 allows the accessory rail at the 12 o'clock position 67 to extend the complete length of the upper receiver 14 as shown in FIG. 4.
  • Referring to FIG. 14, a side elevation view illustrates a non-reciprocating charging handle 280 with forward assist capability. The charging handle 280 includes a body 282 having a groove 284 that engages the charging handle slot 71 (shown in FIG. 3). The charging handle 280 further includes an engagement pin 286, a handle 288, and a detent 290. The charging handle 280 is retained in position on the firearm until desired by a user via the detent 290. The engagement pin 286 extends into the upper receiver through the charging handle access groove 99.
  • The engagement pin 286 further includes a retaining ridge 292 that helps to prevent the engagement pin 286 from rotating in the upper receiver 14. The retaining ridge 292 is biased against the receiver 14 by a spring (not shown). In the biased position of the retaining ridge 292, the engagement pin 286 extends into the upper receiver far enough to abut the charging handle feature 246 of the bolt carrier 126 shown in FIG. 10. When a user chooses to selectively engage the forward assist feature 244 of the bolt carrier 126 shown in FIG. 10, the user pushes the handle 288 in the direction of the retaining ridge 292. Moving the handle 288 in the direction of the retaining ridge 292, moves the engagement pin 286 farther into the upper receiver 14 to engage the forward assist feature 244 of the bolt carrier 126 shown in (FIG. 10). Once the engagement pin 286 engages the forward assist feature 244 of the bolt carrier 126 (shown in FIG. 10), a user may move the handle and thus, the bolt 124 (shown in FIG. 7) to manually lock the bolt 124 against the chamber 122 (shown in FIG. 6). This design of the charging handle 280 allows a user to selectively engage the forward assist feature 244 of the bolt carrier 126, through the positioning of only the handle 288.
  • A method may be used to change the caliber of the firearm 10, described above, using caliber conversion parts. For the firearm 10, the caliber conversion parts include a barrel designed for the desired cartridge in addition to barrel already attached to the firearm 10, which is known in the art, and a bolt designed for the desired cartridge in addition to bolt already connected to the firearm 10, which is also known in the art. For convenience, the caliber conversion parts are referred to in the method as a “second” barrel or a “second” bolt, even though the second barrel and second bolt are almost identical to the barrel 22 and bolt 124 shown in FIG. 6, except for the small changes of dimensions inherent with changes in cartridge type that are well known by those of skill in the art.
  • In some cases, only a second barrel is needed to change the caliber of the firearm 10. Whether a second barrel or a second bolt is needed to change the caliber of the firearm 10, depends on how similar the dimensions of the first cartridge type to the second cartridge type, which information is known to those skilled in the art.
  • Thus, where the bolt of the firearm may be used with the new caliber, the method includes the steps of removing the barrel from the upper receiver, attaching the second barrel to the upper receiver, detaching the ejection buffer from the upper receiver at a first location, and attaching the ejection buffer to the upper receiver at a second location. Where a second bolt and a second barrel are needed to change the caliber of the firearm 10, the method may include the further steps of removing the bolt, bolt carrier, and operating rod from the firearm, disconnecting the operating rod from the bolt carrier to allow removal of the bolt from the bolt carrier, removing the bolt from the bolt carrier, disposing the second bolt in the bolt carrier, connecting the operating rod to the bolt carrier to prevent removal of the second bolt from the bolt carrier, and disposing the second bolt, bolt carrier, and operating rod in the firearm.
  • The present invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims (18)

1. A firearm comprising:
a barrel comprising a beveled barrel retention recess;
a receiver comprising a barrel attachment feature; and
a barrel attachment device having a tapered end, wherein the angle of the tapered end is about the reciprocal of the angle of the beveled barrel retention recess, wherein a portion of the barrel attachment device is disposed in the barrel attachment feature so that the tapered end engages the beveled barrel retention recess to attach the barrel to the receiver.
2. The firearm in claim 1 wherein the angle of the bevel barrel retention recess ranges from about 170 degrees to about 10 degrees.
3. The firearm in claim 1 wherein the angle of the bevel barrel retention recess ranges from about 120 degrees to about 40 degrees.
4. The firearm in claim 1 wherein the angle of the bevel barrel retention recess ranges from about 90 degrees to about 60 degrees.
5. The firearm of claim 1, wherein the receiver comprises a passageway to receive the barrel, the passageway comprising a substantially cylindrical engaging member to engage and support the barrel.
6. The firearm of claim 1, wherein the barrel attachment device comprises a threaded bolt and the barrel attachment feature comprises a threaded hole to engage the threaded bolt.
7. A firearm, comprising:
a barrel attachment device having a tapered end;
a receiver including a barrel attachment feature for receiving the barrel attachment device and allowing the barrel attachment device to extend through the barrel attachment feature; and
a barrel including a beveled barrel retention recess to receive the barrel attachment device and engage the tapered end.
8. The firearm of claim 7, wherein an angle of the tapered end is about the reciprocal of an angle of the beveled barrel retention recess.
9. A firearm, comprising:
a barrel attachment device having a tapered end;
a receiver including a barrel attachment feature for receiving the barrel attachment device and allowing the barrel attachment device to extend through the barrel attachment feature;
a barrel; and
a barrel extension coupled to the barrel and including a beveled barrel retention recess to receive the barrel attachment device and engage the tapered end.
10. The firearm of claim 9, wherein an angle of the tapered end is about the reciprocal of an angle of the beveled barrel retention recess.
11. The firearm of claim 9, wherein the receiver comprises a passageway to receive the barrel, the passageway comprising a substantially cylindrical engaging member to engage and support the barrel.
12. The firearm of claim 9, wherein the barrel attachment device comprises a threaded bolt and the barrel attachment feature comprises a threaded hole to engage the threaded bolt.
13. A firearm comprising:
a barrel;
a receiver; and
a means for securing the barrel to the receiver.
14. The firearm of claim 13 wherein the barrel comprises a barrel extension.
15. The firearm of claim 14 wherein the barrel further comprises a beveled barrel retention recess disposed within the barrel extension.
16. The firearm of claim 13 wherein the receiver comprises a barrel attachment feature.
17. The firearm of claim 16 wherein the barrel attachment feature comprises a threaded hole.
18. The firearm of claim 17 wherein the means for securing the barrel to the receiver comprises threads configured to engage the threaded hole.
US12/208,162 2004-02-13 2008-09-10 Firearm Abandoned US20090000173A1 (en)

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US12/208,162 US20090000173A1 (en) 2004-02-13 2008-09-10 Firearm

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US54458604P 2004-02-13 2004-02-13
US10/911,963 US7596900B2 (en) 2003-08-04 2004-08-04 Multi-caliber ambidextrously controllable firearm
US11/055,580 US7971379B2 (en) 2004-02-13 2005-02-10 Firearm
US12/208,162 US20090000173A1 (en) 2004-02-13 2008-09-10 Firearm

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US12/208,162 Abandoned US20090000173A1 (en) 2004-02-13 2008-09-10 Firearm
US12/209,770 Expired - Fee Related US8096074B2 (en) 2004-02-13 2008-09-12 Firearm
US12/210,878 Active 2025-12-15 US7971382B2 (en) 2004-02-13 2008-09-15 Firearm
US12/246,315 Active 2025-11-28 US7975595B2 (en) 2004-02-13 2008-10-06 Firearm

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US12/210,878 Active 2025-12-15 US7971382B2 (en) 2004-02-13 2008-09-15 Firearm
US12/246,315 Active 2025-11-28 US7975595B2 (en) 2004-02-13 2008-10-06 Firearm

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Cited By (36)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070033851A1 (en) * 2004-06-16 2007-02-15 Paul Hochstrate Automatic or semi-automatic rifle
US20070180984A1 (en) * 2006-02-09 2007-08-09 John Huther Firearm fire control selector
US20090019755A1 (en) * 2007-07-20 2009-01-22 Benelli Armi S.P.A. Modular portable weapon
US20100000396A1 (en) * 2008-07-01 2010-01-07 Adcor Industries, Inc. Firearm having a handle assembly for charging and forward assist
US20100095834A1 (en) * 2004-09-17 2010-04-22 Colt Defense, Llc Firearm having an indirect gas operating system
US20100300277A1 (en) * 2006-02-09 2010-12-02 Colt Defense, Llc Law enforcement carbine with one piece receiver
US7874240B2 (en) 2006-06-23 2011-01-25 Brian Akhavan Firearm operating mechanisms and methods
US20110067285A1 (en) * 2008-07-01 2011-03-24 Adcor Industries, Inc. Firearm having a debris shield for use with a direct gas impingement system
US20110094136A1 (en) * 2009-10-23 2011-04-28 Michael Dwain Zimmerman Rifle upper receiver with integral magazine well
US20120102803A1 (en) * 2010-10-28 2012-05-03 Troy Stephen P Firearm and chassis system
US8210089B2 (en) 2008-07-01 2012-07-03 Adcor Industries, Inc. Firearm having an indirect gas impingement system
US8210090B2 (en) 2008-07-01 2012-07-03 Adcor Industries, Inc. Firearm having an expulsion device
US20120311909A1 (en) * 2011-06-09 2012-12-13 Carson Cheng Multiple rail sighting device
US8342075B2 (en) * 2009-03-10 2013-01-01 Gomez Jesus S Receiver for an autoloading firearm
US8393107B2 (en) 2008-08-26 2013-03-12 Adcor Industries, Inc. Firearm assembly including a first weapon and a second weapon selectively mounted to the first weapon
US20130061737A1 (en) * 2011-09-08 2013-03-14 Michael J. Brown Firearm having a handle assembly for charging and forward assist
US8453364B2 (en) 2006-10-06 2013-06-04 Colt Defense Llc Firearm having a removable hand guard
US20130139424A1 (en) * 2011-12-06 2013-06-06 Benjamin Cory Devine Multi Caliber Quickly Reconfigurable Automatic Machine Gun
US8528458B2 (en) 2011-07-27 2013-09-10 Bernard T. Windauer Pressure-regulating gas block
US8640598B1 (en) 2010-07-19 2014-02-04 Jason Stewart Jackson Sleeve piston for actuating a firearm bolt carrier
US8997620B2 (en) 2012-03-09 2015-04-07 Adcor Industries, Inc. Handle assembly for charging a direct gas impingement firearm
US9003686B2 (en) 2012-02-13 2015-04-14 Adcor Industries, Inc. Hand guard mounting mechanism
US9243856B2 (en) 2008-09-12 2016-01-26 Colt's Manufacturing Company Llc Firearm having a hybrid indirect gas operating system
US9261314B1 (en) 2010-07-19 2016-02-16 Jason Stewart Jackson Sleeve piston for actuating a firearm bolt carrier
USD759780S1 (en) * 2015-01-20 2016-06-21 Roger Wang Low drag forward assist
US9459060B2 (en) 2009-10-05 2016-10-04 Colt's Manufacturing Ip Holding Company Llc Modular firearm
US9506711B2 (en) 2012-07-31 2016-11-29 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US9506702B2 (en) 2014-01-10 2016-11-29 Jv Precision Machine Company Externally loading semi-automatic firearm with integral or non-removable feeding device
US9625232B2 (en) 2013-03-15 2017-04-18 Lwrc International Llc Firearm buffer system and buttstock assembly
US9658011B2 (en) 2011-08-17 2017-05-23 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US9719739B2 (en) 2014-02-06 2017-08-01 Bernard (Bernie) T. Windauer Gas block balancing piston for auto-loading firearm
US9772150B2 (en) 2012-07-31 2017-09-26 Lwrc International Llc Firearm receiver assembly
US9810495B2 (en) 2011-08-17 2017-11-07 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US9816546B2 (en) 2012-07-31 2017-11-14 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US9823031B2 (en) 2009-10-05 2017-11-21 Colt's Manufacturing Ip Holding Company Llc Modular automatic or semi-automatic rifle
EP3372943A1 (en) * 2017-03-07 2018-09-12 Heckler & Koch GmbH Weapon housing and self-loading firearm with same and a method for manufacturing a weapon housing

Families Citing this family (134)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2485710C (en) 2002-05-10 2011-04-19 Karl R. Lewis Monolithic rail platform and bolt assemblies for a firearm
KR100671586B1 (en) * 2003-03-27 2007-01-19 헤클러 운트 코흐 게엠베하 Adapter
US7607424B2 (en) * 2004-02-17 2009-10-27 Planet Eclipse Limited Electro-magnetically operated rotating projectile loader
US20050229465A1 (en) * 2004-04-16 2005-10-20 Serge Dextraze Accessory mount for firearms
US7398616B1 (en) * 2004-05-21 2008-07-15 Robert Weir Adjustable length heavy duty butt stock assembly for a firearm
US7131228B2 (en) * 2004-06-16 2006-11-07 Colt Defense Llc Modular firearm
US7363741B2 (en) * 2004-07-06 2008-04-29 Desomma Frank Hand guard assembly for firearms
US7669359B2 (en) * 2005-06-22 2010-03-02 Surefire, Llc Machine gun accessory mount adapter
DE102005043653A1 (en) 2005-09-13 2007-03-15 Heckler & Koch Gmbh Gas cylinder component and handgun
AT502344B1 (en) * 2005-09-14 2007-12-15 Steyr Mannlicher Holding Gmbh HOUSING FOR A GUN
US8336243B2 (en) * 2007-04-09 2012-12-25 Colt Defense Llc Firearm having a removable hand guard
DE102006009895B3 (en) * 2006-03-03 2007-07-12 S.A.T. Swiss Arms Technology Ag Plug magazine for e.g. repeating rifle, has haul-off unit that is fixed at lower side of magazine such that haul-off unit is detachable together with magazine from hand-gun, where unit is provided with trigger guard and trigger
DE202006011918U1 (en) * 2006-08-03 2006-11-23 Heckler & Koch Gmbh Hinge arrangement for a sighting device of a weapon comprises two pivoting elements joined together using a common coupling element and pivoting a pivoting axis defined by the coupling element
WO2008105960A2 (en) * 2006-10-06 2008-09-04 Colt Defense Llc. Automatic or semiautomatic rifle with folding stock
US9470472B2 (en) * 2007-07-18 2016-10-18 Abrams Airborne Manufacturing Inc. Adaptive configuration for a firearm
ITMI20071474A1 (en) * 2007-07-20 2009-01-21 Benelli Armi Spa CLOSING AND RESET UNIT WITH OSCILLATING SHUTTER AND ROTARY CLOSING HEAD, PARTICULARLY FOR WEAPONS WITH INERTIAL OPERATION USING THE KINETIC ENERGY OF RINCULO
ITMI20071912A1 (en) * 2007-10-04 2009-04-05 Beretta Armi Spa FIRE WEAPON WITH SIMPLIFIED DISASSEMBLY
US8631601B2 (en) 2007-10-05 2014-01-21 Colt Defense, Llc Automatic or semiautomatic rifle with folding clamshell buttstock
US8656622B2 (en) * 2007-10-11 2014-02-25 Ashbury International Group, Inc. Tactical firearm systems and methods of manufacturing same
US7469624B1 (en) * 2007-11-12 2008-12-30 Jason Adams Direct drive retrofit for rifles
US8069600B2 (en) * 2008-01-09 2011-12-06 Browning Multi-caliber bolt for a firearm
US8695260B2 (en) * 2008-02-14 2014-04-15 Lawrence S. Kramer Cartridges and modifications for M16/AR15 rifle
USD676095S1 (en) 2008-10-14 2013-02-12 Ashbury International Group, Inc. Monolithic rail with integral receiver height adapter
USD705885S1 (en) 2008-10-14 2014-05-27 Ashbury International Group, Inc. Monolithic rail with integral receiver height adapter
US8225544B2 (en) * 2009-02-05 2012-07-24 Rubik Darian Mounting rail
US7975419B2 (en) * 2009-02-05 2011-07-12 Rubik Darian Mounting rail
US8104211B2 (en) * 2009-02-05 2012-01-31 Rubik Darian Battery powered mounting rail
USD735288S1 (en) 2009-03-10 2015-07-28 Lwrc International Llc Receiver assembly for an automatic rifle
US8490312B2 (en) 2009-03-24 2013-07-23 Sturm, Ruger & Company, Inc. Quick coupling barrel system for firearm
US9057576B2 (en) 2009-03-24 2015-06-16 Sturm, Ruger & Company, Inc. Firearm with quick coupling barrel system
US8087194B1 (en) 2009-03-24 2012-01-03 Sturm, Ruger & Company, Inc. Firearm barrel retaining system
US8505227B2 (en) 2009-03-24 2013-08-13 Sturm, Ruger & Company, Inc. Firearm with quick coupling barrel interlock system
US8479429B2 (en) 2009-03-24 2013-07-09 Sturm, Ruger & Company, Inc. Firearm with quick coupling barrel system
US8028460B2 (en) * 2009-05-15 2011-10-04 The Otis Patent Trust Integrated rail system and method for making and using same
US8028459B2 (en) * 2009-05-15 2011-10-04 The Otis Patent Trust Integrated rail system and method for making and using same
US20100307042A1 (en) 2009-06-05 2010-12-09 Michael Brent Jarboe Modular firearm stock system
US8176837B1 (en) 2009-10-11 2012-05-15 Jason Stewart Jackson Firearm operating rod
US8689672B2 (en) 2009-10-23 2014-04-08 Charles Blue Cassels Anti-wear buffer device for bolt carrier assembly
US8443711B2 (en) * 2010-01-26 2013-05-21 Leitner-Wise Defense, Inc. Gas operating systems, subsystems, components and processes
US20110209607A1 (en) * 2010-02-02 2011-09-01 St George Charles Apparatus and Method For Improved Weapon Configuration
DE102010009488B3 (en) * 2010-02-26 2011-04-07 Heckler & Koch Gmbh Weapon housing for use in e.g. handgun, has housing shells placed and aligned in mounting plane, where forces acting in or against shoot direction are received from surfaces of connecting pin and positioning recess
DE102010009427B4 (en) 2010-02-26 2012-03-08 Heckler & Koch Gmbh Turnbuckle and weapon
DE102010000617B4 (en) * 2010-03-03 2012-02-23 Al Hail Holding Llc Repeater rifle with replaceable barrel closure group
DE102010011189A1 (en) * 2010-03-11 2011-09-15 Schmeisser Gmbh Automatic weapon
US9038525B2 (en) 2011-01-14 2015-05-26 ArmWest, LLC Firearm
US8973483B2 (en) 2010-03-25 2015-03-10 Arm West, Llc Gas regulator system
CA2793968C (en) 2010-03-25 2017-03-21 ArmWest, LLC High capacity magazine with multiple springs
US8590199B2 (en) 2010-04-15 2013-11-26 22 Evolution Llc Modified bolt assembly with forward assist adaptor for accomodating sub caliber ammunition utilized in an AR-15 type firearm
USD666269S1 (en) * 2010-04-23 2012-08-28 Micheal Dwayne Heath Firearm barrel with integrated flash hider
US8109195B1 (en) * 2010-04-27 2012-02-07 Spence Jeffery D Gas venting system for firearms
US8782941B2 (en) 2010-06-30 2014-07-22 Nisim Zusman Stock for a small arms weapon
US8522467B1 (en) * 2010-09-07 2013-09-03 Jason Christensen Composite hand guard with integral rail
US20120055058A1 (en) * 2010-09-08 2012-03-08 Smith & Wesson Corp. Enhanced service life bolt
US20120198990A1 (en) * 2011-01-13 2012-08-09 Brittin Donald E Handguard system with integral gas tube for gas operated firearms
AU2012205302B2 (en) * 2011-01-14 2016-06-23 ArmWest, LLC Quick Barrel Change Firearm
US9488423B2 (en) 2011-01-14 2016-11-08 Arm West, Llc Firearm systems and methods
US8464454B2 (en) 2011-01-14 2013-06-18 Crosman Corporation Modular adaptive gun
US8661963B2 (en) * 2011-02-11 2014-03-04 Swetal K. Patel Recoil system and method for upper receiver
AT510291B1 (en) * 2011-04-04 2012-03-15 Wilhelm Bubits PISTOL WITH MULTIPLE TRAINS
AT510442B1 (en) 2011-08-24 2012-04-15 Wilhelm Bubits PISTOL WITH LOCK THROUGH LOCKING BODY
ITMI20111578A1 (en) 2011-09-02 2013-03-03 Beretta Armi Spa THERMAL BARRIER FOR FIREARMS AND FIREARMS PROVIDED WITH SUCH THERMAL BARRIERS
EP2780652A1 (en) * 2011-11-16 2014-09-24 SIG Sauer, Inc. Firearm actuation system
US9151558B1 (en) 2011-11-16 2015-10-06 Sig Sauer, Inc. Sear trip bar for a firearm
US10371474B2 (en) 2011-11-17 2019-08-06 Law Tactical, Llc Folding buttstock for firearms with recoil assemblies contained within the buttstock
US8733009B2 (en) 2012-01-06 2014-05-27 Ra Brands, L.L.C. Magazine cutoff
US8769855B2 (en) * 2012-02-19 2014-07-08 Zachary Law Folding stock adaptor for military-style assault rifles and a method for its use
US8893608B2 (en) 2012-07-03 2014-11-25 Lawrence S. Kramer Gas piston system for M16/AR15 rifle or M4 carbine systems
USD697162S1 (en) 2012-08-05 2014-01-07 Sagi Faifer Gun stock
US8800422B2 (en) 2012-08-20 2014-08-12 Ra Brands, L.L.C. Bolt assembly for firearms
US9297609B2 (en) 2012-08-24 2016-03-29 Ra Brands, L.L.C. Firearm with forward grip attachment system
US8844185B2 (en) 2012-08-27 2014-09-30 Ra Brands, L.L.C. Buttstock assembly
WO2014036398A1 (en) * 2012-08-30 2014-03-06 3O.F. Mossberg & Sons, Inc. Method and apparatus for stripping and feeding cartridges
USD704294S1 (en) 2012-09-19 2014-05-06 Ra Brands, L.L.C. Buttstock
US9032860B2 (en) 2012-12-17 2015-05-19 Faxon Firearms, Llc Gas piston operated upper receiver system
USD715885S1 (en) 2013-01-11 2014-10-21 Ra Brands, L.L.C. Portion of a firearm handguard
US8887426B2 (en) 2013-03-15 2014-11-18 Madison Elastomeric extractor member
USD716404S1 (en) 2013-03-15 2014-10-28 John Capps Firearm trigger
US9057572B2 (en) 2013-03-15 2015-06-16 Ra Brands, L.L.C. Firearm extraction system
USD728722S1 (en) 2013-04-29 2015-05-05 Ashbury International Group, Inc. Forend for modular tactical firearms
USD728723S1 (en) 2013-04-29 2015-05-05 Ashbury International Group, Inc. Forend for modular tactical firearms
US20140331535A1 (en) * 2013-05-13 2014-11-13 Jeffrey A. Robinson Lower receiver for a firearm
US8789305B1 (en) * 2013-06-26 2014-07-29 American Tactical Imports, Inc. Hybrid lower receiver for a rifle
AT513980B1 (en) * 2013-07-01 2014-09-15 Steyr Mannlicher Gmbh Firearm
US10330410B2 (en) * 2013-09-05 2019-06-25 Guardian Defense Llc Automatic/semi-automatic rifle assembly for large caliber belted cartridges
US9207032B2 (en) * 2013-10-09 2015-12-08 Smith & Wesson Corp. Slide stop support mechanism
US9429375B2 (en) 2013-10-29 2016-08-30 Patriot Ordnance Factory, Inc. Systems and methods for improved firearm function
US9383154B2 (en) 2013-12-12 2016-07-05 Ra Brands, L.L.C. Gas vent for firearm
USD738981S1 (en) 2013-12-30 2015-09-15 Nisim Zusman Gun stock
US8978284B1 (en) 2013-12-30 2015-03-17 Nisim Zusman Stock and vibration isolator for a small arms weapon
US8984791B1 (en) * 2014-01-08 2015-03-24 Jimi Leslie Adjustable gun stock assembly with modular accessories
US9562730B2 (en) * 2014-01-13 2017-02-07 Ra Brands, L.L.C. Replaceable feed ramp
USD741978S1 (en) 2014-01-23 2015-10-27 Ra Brands, L.L.C. Portion of a firearm handguard
US20150323269A1 (en) * 2014-02-05 2015-11-12 S. I. Defense, Inc. Carrier guide and firearm
US9188400B2 (en) 2014-03-24 2015-11-17 The United States Of America As Represented By The Secretary Of The Navy System and method for charging a weapon
US9581411B2 (en) 2014-04-01 2017-02-28 Nisim Zusman Stock and detachable accessory housing for a small arms weapon
USD747427S1 (en) 2014-07-15 2016-01-12 Nisim Zusman Gun stock with accessory rail
USD748216S1 (en) 2014-07-15 2016-01-26 Nisim Zusman Gun stock
USD745622S1 (en) 2014-05-15 2015-12-15 Nisim Zusman Gun stock
US20160033234A1 (en) * 2014-07-31 2016-02-04 Joseph A. Swift Composite Interconnect Accessory Rail System
USD883421S1 (en) 2014-09-05 2020-05-05 Guardian Defense, LLC Bolt carrier for a rifle
US20160187086A1 (en) * 2014-12-25 2016-06-30 Mehmet ÇELER Detach - reassembly system with slide for semi-automatic hunting shotguns and rifles
US10012462B2 (en) 2015-01-20 2018-07-03 Patriot Ordnance Factory, Inc. Bolt carrier support system
US10197348B2 (en) 2015-01-20 2019-02-05 Patriot Ordnance Factory, Inc. Adjustable gas block system
WO2016138197A1 (en) * 2015-02-26 2016-09-01 Sturm, Ruger & Company, Inc. Bolt for bolt action rifles
US9541339B2 (en) 2015-03-26 2017-01-10 American Defense Manufacturing, Llc Ambidextrously operable firearm receiver assembly
KR102362955B1 (en) * 2015-10-16 2022-02-14 가부시키가이샤 도쿄 마루이 bolt stop shock absorber in gun
US10578379B2 (en) 2015-11-04 2020-03-03 Patriot Ordinance Factory, Inc. Firearm bolt carrier assembly kit
US10184739B2 (en) * 2015-12-03 2019-01-22 J & K Ip Assets, Llc Firearm bolt assembly for a self-loading firearm
US9664465B1 (en) 2015-12-15 2017-05-30 Smith & Wesson Corp. Bolt carrier bearing tube for rifle receiver
USD787005S1 (en) 2016-01-18 2017-05-16 Patriot Ordnance Factory, Inc. Firearm upper receiver
US10132587B2 (en) 2016-01-19 2018-11-20 Patriot Ordnance Factory, Inc. Reduced weight firearm
USD819766S1 (en) 2016-03-07 2018-06-05 Edward Farris Non-reciprocating side charging upper receiver
US9897404B2 (en) 2016-03-18 2018-02-20 WHG Properties, LLC Recoil spring for a firearm
US10001336B2 (en) 2016-09-16 2018-06-19 Ambimjb, Llc Auto sear actuation linkage for compact AR-platform firearm
US10488136B2 (en) 2016-09-23 2019-11-26 ArmWest, LLC Selective fire firearm systems and methods
US11656042B2 (en) * 2016-09-28 2023-05-23 Claude A. Durham, III Bolt assembly
US10677548B2 (en) * 2017-06-02 2020-06-09 Gibbens Engineering Group, LLC Lower receiver
USD847933S1 (en) 2017-06-09 2019-05-07 Maxim Defense Industries, LLC Stock for a gun
USD865898S1 (en) 2017-09-06 2019-11-05 Maxim Defense Industries, LLC Stock for a gun
USD883419S1 (en) 2017-09-06 2020-05-05 Maxim Defense Industries, LLC Stock for a gun
US11112199B2 (en) * 2017-11-17 2021-09-07 Jorge Pizano Slide action rifle with a bolt carrier locking mechanism external to the receiver
US10690425B2 (en) * 2017-12-22 2020-06-23 Charles B. Cassels Firearm with locked breech rotating bolt pistol
US10436535B1 (en) 2018-01-30 2019-10-08 22 Evolution Llc Auto sear such as for use with any AR10 M16 or other midsize firearm platform
US11204210B2 (en) * 2018-08-21 2021-12-21 Osprey Armament, LLC Semi-automatic rifle and retrofit magazine
US11041687B2 (en) 2018-12-10 2021-06-22 Maxim Defense Industries, LLC Gas block and barrel assembly and method of fabricating same
USD953470S1 (en) 2019-01-10 2022-05-31 Maxim Defense Industries, LLC Upper assembly, handguard, lower receiver, and stock for a gun
US11112192B2 (en) 2019-01-21 2021-09-07 Ares Defense Systems Inc. Ammunition convertible firearm
US11624583B2 (en) 2019-07-16 2023-04-11 Sagi Faifer Variably adjustable stock for a gun and apparatus and method for adjustment of same
USD907157S1 (en) 2019-07-16 2021-01-05 Sagi Faifer Stock for a gun
EP3800427A1 (en) 2019-10-04 2021-04-07 Glock Technology GmbH Firearm with an ejector
US11402169B1 (en) 2020-03-31 2022-08-02 Kevin Michael Sohegian Switch barrel rifle with adjustable headspace
US20210396483A1 (en) * 2020-06-19 2021-12-23 Shari LeGate, Ltd Bolt carrier for magazine-fed firearm
US11187473B1 (en) 2021-02-01 2021-11-30 A. W. Richey Firearm
US11313633B1 (en) 2021-04-13 2022-04-26 A. W. Richey Firearm

Citations (44)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2422532A (en) * 1943-12-11 1947-06-17 Dehm Edward Bolt-actuated cartridge feeding means for rifles
US3386336A (en) * 1966-03-30 1968-06-04 Colt S Inc Convertible machine gun for rightand left-hand cartridge feed and operation
US3618457A (en) * 1969-11-25 1971-11-09 Arthur Miller Rotary and sliding firearm bolt with eternal cam
US4128042A (en) * 1975-12-30 1978-12-05 Atchisson Maxwell G Automatic bolt catch release apparatus for firearm
US4227439A (en) * 1979-03-27 1980-10-14 Ares, Inc. Anti-bounce apparatus for reciprocating bolt assemblies of automatic cannon
US4231177A (en) * 1975-10-31 1980-11-04 U.S. Armament Corporation Automatic and semiautomatic small caliber conversion system
US4358986A (en) * 1979-09-11 1982-11-16 Charles Giorgio Rifle bolt assemblies
US4471551A (en) * 1981-02-27 1984-09-18 Sig Schweizerische Industrie-Gesellschaft Safety device for firearms
US4505182A (en) * 1980-12-11 1985-03-19 Chartered Industries Of Singapore Private Ltd. Firearm trigger mechanism
US4651445A (en) * 1985-09-03 1987-03-24 Hannibal Alan J Composite sole for a shoe
US4942802A (en) * 1987-09-24 1990-07-24 Ares, Inc. Convertible, belt/clip-fed automatic gun with positive shell casing ejection
US5155284A (en) * 1989-10-18 1992-10-13 Israel Military Industries Ltd Machine guns barrel locking mechanism
US5452534A (en) * 1994-08-12 1995-09-26 Lambie; Michael G. Receiver for firearm
US5519954A (en) * 1995-06-19 1996-05-28 Garrett; Robert H. Ambidextrous magazine release mechanism for firearms
US5540008A (en) * 1993-11-03 1996-07-30 Erma Werke Waffen & Maschf System bearing on a small arm
US5664355A (en) * 1995-12-27 1997-09-09 Remington Arms Company, Inc. Detachable ammunition magazine
US5706599A (en) * 1995-05-18 1998-01-13 Modern Muzzleloading, Inc. Rifle with interchangeable barrel
US5802755A (en) * 1997-02-05 1998-09-08 The United States Of America As Represented By The Secretary Of The Army Ratchet-locking collar
US5900577A (en) * 1997-01-29 1999-05-04 Zdf Import Export Inc Modular, multi-caliber weapon system
US5907919A (en) * 1996-12-31 1999-06-01 Remington Arms Company, Inc. Barrel and receiver assembly
US6070352A (en) * 1998-11-12 2000-06-06 Colt's Manufacturing Company, Inc. Firearm magazine cartridge converter
US6418655B1 (en) * 1999-08-19 2002-07-16 Ira M. Kay Underbarrel shotgun
US20020139241A1 (en) * 2000-07-24 2002-10-03 Butler Lawrence V. Semi-automatic gas-operated shotgun
US20020162266A1 (en) * 2001-01-31 2002-11-07 Clay David Richard Combination barrel adjustment and magazine cutoff for a takedown firearm
US6510778B1 (en) * 2000-12-28 2003-01-28 Custom Shooting Technologies, Inc. Automatic bolt hold-open assembly
US20030066226A1 (en) * 2001-10-08 2003-04-10 Martin James W. Self-locking firearm bolt action
US6606812B1 (en) * 2002-06-13 2003-08-19 Mack W. Gwinn, Jr. Firearm barrel change apparatus
US6634274B1 (en) * 2000-12-11 2003-10-21 Geoffrey Andrew Herring Firearm upper receiver assembly with ammunition belt feeding capability
US6655372B1 (en) * 2002-04-17 2003-12-02 Damion J. Field Quick detachable gun barrel assembly
US20040020092A1 (en) * 2002-02-04 2004-02-05 Christensen Craig A. Firearm with fixed cartridge magazine top
US6848351B1 (en) * 2002-05-07 2005-02-01 Robert B. Davies Rifle
US6907814B2 (en) * 2000-02-25 2005-06-21 Heckler & Koch, Gmbh Automatic firearms with a detachable breech lock
US6910404B2 (en) * 2003-05-13 2005-06-28 General Dynamics Armament And Technical Products, Inc. Gun bolt locking mechanism
US6931978B1 (en) * 2004-02-19 2005-08-23 Snc Technologies Inc. Rebound attenuation device for automatic firearms
US20050188590A1 (en) * 2003-08-26 2005-09-01 Jerry Baber Breech construction for firearms
US20050188591A1 (en) * 2004-01-30 2005-09-01 Stone Jeffrey W. Barrel assembly and attachment system
US20050223613A1 (en) * 2003-01-27 2005-10-13 Terrence Bender Gas operated action for auto-loading firearms
US20050229463A1 (en) * 2004-04-14 2005-10-20 Paul Tashjian Firearm assembly
US20060236582A1 (en) * 2002-05-10 2006-10-26 Lewis Karl R Monolithic rail platform and bolt assemblies for a firearm
US20070033851A1 (en) * 2004-06-16 2007-02-15 Paul Hochstrate Automatic or semi-automatic rifle
US7219462B2 (en) * 2004-02-09 2007-05-22 Rock River Arms, Inc. Receiver assembly for firearm
US7219461B1 (en) * 2003-05-23 2007-05-22 Ra Brands, L.L.C. Bolt assembly with locking system
US7302881B1 (en) * 2005-06-07 2007-12-04 Magnum Research, Inc. Conversion kit and method for a ruger 10/22 semi-automatic .22 caliber rim fire rifle to shoot .17 mach 2 cartridges
US7313883B2 (en) * 2004-07-27 2008-01-01 Leitner-Wise Rifle Company, Inc. Modular receiver system

Family Cites Families (99)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US521202A (en) * 1894-06-12 Folding gun
FR573151A (en) * 1923-11-12 1924-06-19 Dansk Rekylriffel Syndikat As Interchangeable barrel machine gun enhancements
DE677948C (en) * 1935-09-25 1939-07-05 Armes De Guerre Fab Nat Machine gun
US2365306A (en) * 1940-10-15 1944-12-19 High Standard Mfg Corp Self-loading takedown firearm
US2387691A (en) * 1942-09-19 1945-10-23 Oswald O Sunderland Gun
BE510503A (en) * 1952-04-07
DE1890933U (en) 1964-01-23 1964-04-09 Heckler & Koch Gmbh AUTOMATIC FIRE ARM.
ES379338A1 (en) 1969-04-29 1973-04-16 Beretta Armi Spa Automatic rifle
US3593452A (en) 1969-08-18 1971-07-20 Colt S Inc Bolt stop for firearms
US3630118A (en) * 1969-09-05 1971-12-28 Stoner Eugene Two-step ammunition feeder
CH514116A (en) 1970-02-04 1971-10-15 Heckler & Koch Gmbh Self-loading firearm
US3648562A (en) * 1970-04-28 1972-03-14 August F Loeble Safety cam pin assembly
US3688640A (en) 1970-05-15 1972-09-05 Mossberg & Sons O F Repeating firearm with bolt-open latch
US3776095A (en) 1971-11-05 1973-12-04 M Atchisson Weapon conversion bolt assembly device
BE778024A (en) * 1972-01-14 1972-07-14 Herstal Sa GAME CATCHING DEVICE FOR HUNTING RIFLE LOCK KEY
US3771415A (en) * 1972-02-07 1973-11-13 Colt Ind Operating Corp Rifle conversion assembly
US3850076A (en) 1972-05-03 1974-11-26 M Atchisson Firearm apparatus
US3857323A (en) 1972-10-02 1974-12-31 Sturm Ruger & Co Slide guide for rifles
GB1420626A (en) 1972-10-02 1976-01-07 Sturm Ruger & Co Auto-loading firearm
FI48878C (en) * 1973-01-26 1975-01-10 Valmet Oy Cartridge cartridge puller for rotary guns.
US3846928A (en) 1973-08-20 1974-11-12 Strum Ruger & Co Inc Bolt latch for auto loading firearm
US4066000A (en) * 1974-04-25 1978-01-03 Brunswick Corporation Machine gun
US3924512A (en) * 1974-05-07 1975-12-09 Us Army Removable lockplate to preclude selection of automatic firing
US4023465A (en) * 1975-06-27 1977-05-17 Inskip Thomas C Firearm
US4022105A (en) * 1975-09-03 1977-05-10 The United States Of America As Represented By The Secretary Of The Army Automatic weapon firing mechanism
US3999461A (en) 1975-09-03 1976-12-28 The United States Of America As Represented By The Secretary Of The Army Modular lightweight squad automatic weapon system
US4058922A (en) 1975-09-26 1977-11-22 The United States Of America As Represented By The Secretary Of The Army Rifle adapter assembly
US4098016A (en) * 1975-10-31 1978-07-04 U.S. Armament Corporation Automatic and semiautomatic small caliber conversion system
JPS5282000A (en) 1975-12-27 1977-07-08 Shiyaapu Raifuru Kk Gas or gas accumulated continuously shooting gun
US4057003A (en) 1975-12-30 1977-11-08 Atchisson Maxwell G Open bolt conversion apparatus
US4028993A (en) 1976-02-23 1977-06-14 The United States Of America As Represented By The Secretary Of The Army Cycle firing rate reducing assembly for automatic weapons
US4056038A (en) 1976-05-12 1977-11-01 Rath Hans M Dual purpose semi-automatic convertible rifle
US4044487A (en) * 1976-05-27 1977-08-30 Remington Arms Company, Inc. Rotary port cover
US4169329A (en) * 1977-09-06 1979-10-02 Atchisson Maxwell G Weapon conversion apparatus
US4213177A (en) * 1978-04-24 1980-07-15 Texas Instruments Incorporated Eight bit standard connector bus for sixteen bit microcomputer using mirrored memory boards
US4213261A (en) * 1978-06-27 1980-07-22 James P. Claypool Breech locking mechanism
US4244273A (en) 1978-12-04 1981-01-13 Langendorfer Plastics Corporation Rifle modification
DE2905770C2 (en) 1979-02-15 1984-01-05 Carl Walther Gmbh, 7900 Ulm Magazine release
US4389919A (en) 1980-02-14 1983-06-28 Remington Arms Company, Inc. Firing pin block for firearm with a rotary breech bolt
EP0054088B1 (en) 1980-12-11 1985-07-17 Chartered Industries Of Singapore Private Limited Improvements in or relating to gas operated, automatic or semi-automatic guns
US4502367A (en) * 1980-12-11 1985-03-05 Chartered Industries Of Singapore Private Ltd. Firearms bolt carrier assembly
IT1144361B (en) 1981-05-12 1986-10-29 Roberto Teppa AUTOMATIC FIREARM
US4398448A (en) * 1981-07-31 1983-08-16 The United States Of America As Represented By The Secretary Of The Army Buffered bolt assembly
DE3130761C2 (en) 1981-08-04 1984-01-05 Heckler & Koch Gmbh, 7238 Oberndorf Automatic handgun or machine gun
US4433610A (en) 1981-08-06 1984-02-28 Colt Industries Operating Corp Open bolt firing mechanism for automatic firearm
US4438678A (en) 1981-10-23 1984-03-27 Sturm, Ruger & Company, Inc. Bolt stop and cartridge ejector for auto-loading rifle
SE430435B (en) * 1981-12-14 1983-11-14 Flodman Guns Kb GUIDANCE FOR A SWITCH
US4893547A (en) 1981-12-31 1990-01-16 Atchisson Maxwell G Bolt mechanism for fire arm
US4693170A (en) 1984-08-08 1987-09-15 Atchisson Maxwell G Firing mechanism for firearm
US4429479A (en) 1982-04-26 1984-02-07 J.F.S., Inc. Magazine latch release mechanism
US4563937A (en) * 1983-01-04 1986-01-14 Magnum Research, Inc. Gas actuated pistol
US4521985A (en) 1983-05-16 1985-06-11 Smith Alan K Ambidextrous gun magazine release
USH87H (en) * 1983-07-18 1986-07-01 The United States Of America As Represented By The Secretary Of The Army One piece ejector/ejector spring for cartridge firing weapons
US4599818A (en) 1983-08-24 1986-07-15 Bangor Punta Corporation Magazine catch
US4579034A (en) 1983-09-15 1986-04-01 Holloway Robert C Bolt assembly and cartridge feed mechanism for automatic firearm
US4562659A (en) 1983-09-26 1986-01-07 Yoave Neta Automatic firearm
US4835892A (en) 1984-06-25 1989-06-06 Sturm, Ruger & Company, Inc. Magazine latch for pistol
US4713902A (en) 1985-10-23 1987-12-22 Kevin Wigton Ambidextrous or left-handed magazine catch for a pistol
US4972617A (en) * 1986-06-19 1990-11-27 Barbara Major Automatic firearm
US4756228A (en) 1986-06-24 1988-07-12 Ameram Corporation Repeating weapon actuating spring and guide
US4765224A (en) 1986-08-15 1988-08-23 Morris Michael C Automatic rifle gas system
US4872391A (en) 1987-06-02 1989-10-10 Ares, Inc. Gun for firing telescoped ammunition, plus searing means
US4791851A (en) 1987-06-02 1988-12-20 Ares, Inc. Gun for firing telescoped ammunition
US4759144A (en) 1987-07-06 1988-07-26 Egan James W Ambidextrous magazine release
GB8717722D0 (en) 1987-07-27 1987-11-18 Sterling Armament Co Ltd Bolt assembly for self-loading gun
US4867040A (en) 1987-11-02 1989-09-19 Barrett Ronnie G Self-unlocking device for recoiling bolt carrier and barrel in a semi-automatic rifle
US4932148A (en) 1989-01-23 1990-06-12 Barrett Ronnie G Shoulder-fired semi-automatic rifle
US4920678A (en) 1989-05-04 1990-05-01 Brown Michael W Conversion kit for semiautomatic weapons
US5046275A (en) * 1989-05-04 1991-09-10 Brown Michael W Conversion kit for semiautomatic weapons
US5038666A (en) * 1989-11-20 1991-08-13 Barbara Major Automatic firearm
US5123329A (en) 1989-12-15 1992-06-23 Irwin Robert M Self-actuating blow forward firearm
US5588241A (en) 1990-02-26 1996-12-31 Hurley; William W. High capacity conversion magazine
US5103714A (en) 1991-06-17 1992-04-14 Lafrance Timothy F Retro-fit gas system for controlling the firing rate of the Colt M16 automatic carbine
US5305539A (en) * 1992-07-24 1994-04-26 Kent Von Kuster Collapsible firearm device
US5383389A (en) * 1993-06-29 1995-01-24 Martin Marietta Corporation Ammunition indexing mechanism
US5663522A (en) 1993-08-20 1997-09-02 Kuehl; Robert Arnold M60 semi-automatic conversion
US5581926A (en) 1994-09-16 1996-12-10 Sentinel Arms, B.G. Manually actuated rifle
US5551179A (en) * 1995-01-06 1996-09-03 Young; Daniel H. Bolt carrier
US5634288A (en) 1995-01-20 1997-06-03 Martel; Phillip C. One-piece gas tube for SKS rifle
US5770814A (en) * 1996-05-09 1998-06-23 Defense Technologies Limited Firing rate regulating mechanism
AT411296B (en) * 1996-09-10 2003-11-25 Steyr Daimler Puch Ag HANDGUN WITH LIGHTWEIGHT CASE
US5680724A (en) 1996-11-27 1997-10-28 Peterken; William H. Firearm safety and dry-fire device
US6019024A (en) 1998-01-26 2000-02-01 Zdf Import Export, Inc. Compact operating system for automatic rifles
US6012246A (en) 1998-01-26 2000-01-11 Zdf Import Export Inc. Buttstock for firearm with ambidextrous sling attachment and removable butt plate
US6101918A (en) 1998-05-12 2000-08-15 Akins; William Method and apparatus for accelerating the cyclic firing rate of a semi-automatic firearm
US6484430B1 (en) 1999-01-27 2002-11-26 Zdf Import/Export, Inc. Multi-lugged bolt carrier and barrel for rifles
DE19903327B4 (en) * 1999-01-28 2004-08-12 Heckler & Koch Gmbh Locking device for a handgun
US6625916B1 (en) * 1999-11-04 2003-09-30 Snc Technologies Inc. Conversion of firearms to fire reduced-energy ammunition
US6293040B1 (en) * 1999-08-27 2001-09-25 Defense Procurement Manufacturing Services, Inc. Interchangeable weapon receiver for alternate ammunition
US6820533B2 (en) 2001-11-13 2004-11-23 Dale Schuerman Bolt action rifle
US6609319B1 (en) * 2002-10-07 2003-08-26 Knights Armament Company Bolt assemblies for firearms
NO20032350A (en) 2003-05-26 2004-06-07 Tom Asle Henninge Locking trigger for firearms of the type Heckler & Koch G36 and SL8
CA2583412C (en) * 2004-09-17 2013-02-19 Colt Defense Llc Firearm having an indirect gas operating system
US7428795B2 (en) * 2005-02-11 2008-09-30 Herring Geoffrey A Receiver for firearm
WO2008060310A2 (en) * 2006-02-09 2008-05-22 Colt Defense Llc Law enforcement carbine with one piece receiver
US7461581B2 (en) * 2006-07-24 2008-12-09 Lwrcinternational, Llc Self-cleaning gas operating system for a firearm
US7753679B1 (en) * 2006-12-29 2010-07-13 Schuetz Brian D Non-firing training rifle
US7627974B2 (en) * 2007-03-02 2009-12-08 Wilsons Gunshop Inc Bridged extractor spring for firearms
US8210089B2 (en) * 2008-07-01 2012-07-03 Adcor Industries, Inc. Firearm having an indirect gas impingement system

Patent Citations (48)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2422532A (en) * 1943-12-11 1947-06-17 Dehm Edward Bolt-actuated cartridge feeding means for rifles
US3386336A (en) * 1966-03-30 1968-06-04 Colt S Inc Convertible machine gun for rightand left-hand cartridge feed and operation
US3618457A (en) * 1969-11-25 1971-11-09 Arthur Miller Rotary and sliding firearm bolt with eternal cam
US4231177A (en) * 1975-10-31 1980-11-04 U.S. Armament Corporation Automatic and semiautomatic small caliber conversion system
US4128042A (en) * 1975-12-30 1978-12-05 Atchisson Maxwell G Automatic bolt catch release apparatus for firearm
US4227439A (en) * 1979-03-27 1980-10-14 Ares, Inc. Anti-bounce apparatus for reciprocating bolt assemblies of automatic cannon
US4358986A (en) * 1979-09-11 1982-11-16 Charles Giorgio Rifle bolt assemblies
US4505182A (en) * 1980-12-11 1985-03-19 Chartered Industries Of Singapore Private Ltd. Firearm trigger mechanism
US4471551A (en) * 1981-02-27 1984-09-18 Sig Schweizerische Industrie-Gesellschaft Safety device for firearms
US4651445A (en) * 1985-09-03 1987-03-24 Hannibal Alan J Composite sole for a shoe
US4942802A (en) * 1987-09-24 1990-07-24 Ares, Inc. Convertible, belt/clip-fed automatic gun with positive shell casing ejection
US5155284A (en) * 1989-10-18 1992-10-13 Israel Military Industries Ltd Machine guns barrel locking mechanism
US5540008A (en) * 1993-11-03 1996-07-30 Erma Werke Waffen & Maschf System bearing on a small arm
US5452534A (en) * 1994-08-12 1995-09-26 Lambie; Michael G. Receiver for firearm
US5706599A (en) * 1995-05-18 1998-01-13 Modern Muzzleloading, Inc. Rifle with interchangeable barrel
US5519954A (en) * 1995-06-19 1996-05-28 Garrett; Robert H. Ambidextrous magazine release mechanism for firearms
US5664355A (en) * 1995-12-27 1997-09-09 Remington Arms Company, Inc. Detachable ammunition magazine
US5907919A (en) * 1996-12-31 1999-06-01 Remington Arms Company, Inc. Barrel and receiver assembly
US5900577A (en) * 1997-01-29 1999-05-04 Zdf Import Export Inc Modular, multi-caliber weapon system
US5802755A (en) * 1997-02-05 1998-09-08 The United States Of America As Represented By The Secretary Of The Army Ratchet-locking collar
US6070352A (en) * 1998-11-12 2000-06-06 Colt's Manufacturing Company, Inc. Firearm magazine cartridge converter
US6418655B1 (en) * 1999-08-19 2002-07-16 Ira M. Kay Underbarrel shotgun
US6907814B2 (en) * 2000-02-25 2005-06-21 Heckler & Koch, Gmbh Automatic firearms with a detachable breech lock
US20020139241A1 (en) * 2000-07-24 2002-10-03 Butler Lawrence V. Semi-automatic gas-operated shotgun
US6681677B2 (en) * 2000-12-11 2004-01-27 Geoffrey A. Herring Method of reconfiguring a firearm receiver system for receiving magazine-fed ammunition and belt-fed ammunition
US20050011345A1 (en) * 2000-12-11 2005-01-20 Herring Geoffrey A. Firearm bolt catch assembly
US6722255B2 (en) * 2000-12-11 2004-04-20 Geoffrey A. Herring Apparatus and method for actuating a bolt carrier group of a receiver assembly
US6634274B1 (en) * 2000-12-11 2003-10-21 Geoffrey Andrew Herring Firearm upper receiver assembly with ammunition belt feeding capability
US6510778B1 (en) * 2000-12-28 2003-01-28 Custom Shooting Technologies, Inc. Automatic bolt hold-open assembly
US20020162266A1 (en) * 2001-01-31 2002-11-07 Clay David Richard Combination barrel adjustment and magazine cutoff for a takedown firearm
US20030066226A1 (en) * 2001-10-08 2003-04-10 Martin James W. Self-locking firearm bolt action
US20040020092A1 (en) * 2002-02-04 2004-02-05 Christensen Craig A. Firearm with fixed cartridge magazine top
US6655372B1 (en) * 2002-04-17 2003-12-02 Damion J. Field Quick detachable gun barrel assembly
US6848351B1 (en) * 2002-05-07 2005-02-01 Robert B. Davies Rifle
US20060236582A1 (en) * 2002-05-10 2006-10-26 Lewis Karl R Monolithic rail platform and bolt assemblies for a firearm
US6606812B1 (en) * 2002-06-13 2003-08-19 Mack W. Gwinn, Jr. Firearm barrel change apparatus
US20050223613A1 (en) * 2003-01-27 2005-10-13 Terrence Bender Gas operated action for auto-loading firearms
US6910404B2 (en) * 2003-05-13 2005-06-28 General Dynamics Armament And Technical Products, Inc. Gun bolt locking mechanism
US7219461B1 (en) * 2003-05-23 2007-05-22 Ra Brands, L.L.C. Bolt assembly with locking system
US20050188590A1 (en) * 2003-08-26 2005-09-01 Jerry Baber Breech construction for firearms
US7032340B2 (en) * 2003-08-26 2006-04-25 Jerry Baber Breech construction for firearms
US20050188591A1 (en) * 2004-01-30 2005-09-01 Stone Jeffrey W. Barrel assembly and attachment system
US7219462B2 (en) * 2004-02-09 2007-05-22 Rock River Arms, Inc. Receiver assembly for firearm
US6931978B1 (en) * 2004-02-19 2005-08-23 Snc Technologies Inc. Rebound attenuation device for automatic firearms
US20050229463A1 (en) * 2004-04-14 2005-10-20 Paul Tashjian Firearm assembly
US20070033851A1 (en) * 2004-06-16 2007-02-15 Paul Hochstrate Automatic or semi-automatic rifle
US7313883B2 (en) * 2004-07-27 2008-01-01 Leitner-Wise Rifle Company, Inc. Modular receiver system
US7302881B1 (en) * 2005-06-07 2007-12-04 Magnum Research, Inc. Conversion kit and method for a ruger 10/22 semi-automatic .22 caliber rim fire rifle to shoot .17 mach 2 cartridges

Cited By (85)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8051595B2 (en) 2004-06-16 2011-11-08 Colt Defense, Llc Automatic or semi-automatic rifle
US8640372B2 (en) 2004-06-16 2014-02-04 Colt Defense, Llc Automatic or semi-automatic rifle
US20070033851A1 (en) * 2004-06-16 2007-02-15 Paul Hochstrate Automatic or semi-automatic rifle
US9612072B2 (en) 2004-06-16 2017-04-04 Colt's Manufacturing Ip Holding Company Llc Automatic or semi-automatic rifle
US9279632B2 (en) 2004-06-16 2016-03-08 Colt's Manufacturing Ip Holding Company Llc Automatic or semi-automatic rifle
US20100095834A1 (en) * 2004-09-17 2010-04-22 Colt Defense, Llc Firearm having an indirect gas operating system
US7934447B2 (en) 2004-09-17 2011-05-03 Colt Defense Llc Firearm having an indirect gas operating system
US8943948B2 (en) 2004-09-17 2015-02-03 Colt's Manufacturing Company Llc Firearm having an indirect gas operating system
US20100300277A1 (en) * 2006-02-09 2010-12-02 Colt Defense, Llc Law enforcement carbine with one piece receiver
US20070180984A1 (en) * 2006-02-09 2007-08-09 John Huther Firearm fire control selector
US9562733B2 (en) 2006-02-09 2017-02-07 Colt's Manufacturing Ip Holding Company Llc Firearm fire control selector
US7938055B2 (en) 2006-02-09 2011-05-10 Colt Defense Llc Law enforcement carbine with one piece receiver
US8783160B2 (en) 2006-02-09 2014-07-22 Colt's Manufacturing Company Llc Firearm with gas operating system
US8505433B2 (en) 2006-02-09 2013-08-13 Colt Defense, Llc Firearm with gas operating system
US8756847B2 (en) 2006-02-09 2014-06-24 Colt Defense Llc Firearm fire control selector
US7874240B2 (en) 2006-06-23 2011-01-25 Brian Akhavan Firearm operating mechanisms and methods
US9228799B2 (en) 2006-10-06 2016-01-05 Colt's Manufacturing Company Llc Firearm having a removable hand guard
US8919025B2 (en) 2006-10-06 2014-12-30 Colt's Manufacturing Company Llc Firearm having a removable hand guard
US8453364B2 (en) 2006-10-06 2013-06-04 Colt Defense Llc Firearm having a removable hand guard
US8230632B2 (en) * 2007-07-20 2012-07-31 Benelli Armi S.P.A. Modular portable weapon
US20090019755A1 (en) * 2007-07-20 2009-01-22 Benelli Armi S.P.A. Modular portable weapon
US8561517B2 (en) 2008-07-01 2013-10-22 Adcor Industries, Inc. Firearm having a handle assembly for charging and forward assist
US7937870B2 (en) 2008-07-01 2011-05-10 Adcor Industries, Inc. Firearm having a debris shield for use with a direct gas impingement system
US8800192B2 (en) 2008-07-01 2014-08-12 Adcor Industries, Inc. Debris shield for a firearm
US20100000396A1 (en) * 2008-07-01 2010-01-07 Adcor Industries, Inc. Firearm having a handle assembly for charging and forward assist
US8393103B2 (en) 2008-07-01 2013-03-12 Adcor Industries, Inc. Firearm having a debris shield
US20110067285A1 (en) * 2008-07-01 2011-03-24 Adcor Industries, Inc. Firearm having a debris shield for use with a direct gas impingement system
US8393102B2 (en) 2008-07-01 2013-03-12 Adcor Industries, Inc. Magazine repair system for firearm
US8210089B2 (en) 2008-07-01 2012-07-03 Adcor Industries, Inc. Firearm having an indirect gas impingement system
US8210090B2 (en) 2008-07-01 2012-07-03 Adcor Industries, Inc. Firearm having an expulsion device
US8156854B2 (en) 2008-07-01 2012-04-17 Adcor Industries, Inc. Firearm having a handle assembly for charging and forward assist
US9134082B2 (en) 2008-07-01 2015-09-15 Adcor Industries, Inc. Firearm having an indirect gas impingement system
US8561335B2 (en) 2008-07-01 2013-10-22 Adcor Industries, Inc. Firearm including improved hand guard
US9109848B2 (en) * 2008-07-01 2015-08-18 Adcor Industries, Inc. Firearm having a handle assembly for charging
US8141285B2 (en) 2008-07-01 2012-03-27 Adcor Industries, Inc. Firearm including improved hand guard
US8393107B2 (en) 2008-08-26 2013-03-12 Adcor Industries, Inc. Firearm assembly including a first weapon and a second weapon selectively mounted to the first weapon
US9243856B2 (en) 2008-09-12 2016-01-26 Colt's Manufacturing Company Llc Firearm having a hybrid indirect gas operating system
US8342075B2 (en) * 2009-03-10 2013-01-01 Gomez Jesus S Receiver for an autoloading firearm
US9459060B2 (en) 2009-10-05 2016-10-04 Colt's Manufacturing Ip Holding Company Llc Modular firearm
US10101101B2 (en) 2009-10-05 2018-10-16 Colt's Manufacturing Ip Holding Company Llc Modular firearm
US9823031B2 (en) 2009-10-05 2017-11-21 Colt's Manufacturing Ip Holding Company Llc Modular automatic or semi-automatic rifle
US8484877B2 (en) * 2009-10-23 2013-07-16 Michael Dwain Zimmerman Rifle upper receiver with integral magazine well
US20110094136A1 (en) * 2009-10-23 2011-04-28 Michael Dwain Zimmerman Rifle upper receiver with integral magazine well
US9261314B1 (en) 2010-07-19 2016-02-16 Jason Stewart Jackson Sleeve piston for actuating a firearm bolt carrier
US8640598B1 (en) 2010-07-19 2014-02-04 Jason Stewart Jackson Sleeve piston for actuating a firearm bolt carrier
US20120102803A1 (en) * 2010-10-28 2012-05-03 Troy Stephen P Firearm and chassis system
US9140520B2 (en) * 2010-10-28 2015-09-22 John M. Lopes Firearm and chassis system
US20120311909A1 (en) * 2011-06-09 2012-12-13 Carson Cheng Multiple rail sighting device
US8505228B2 (en) * 2011-06-09 2013-08-13 NcStar Inc. Multiple rail sighting device
US8528458B2 (en) 2011-07-27 2013-09-10 Bernard T. Windauer Pressure-regulating gas block
US11067352B2 (en) 2011-08-17 2021-07-20 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US11662169B2 (en) 2011-08-17 2023-05-30 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US11828560B2 (en) 2011-08-17 2023-11-28 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US11493292B2 (en) 2011-08-17 2022-11-08 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US10598452B2 (en) 2011-08-17 2020-03-24 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US9658011B2 (en) 2011-08-17 2017-05-23 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US10309739B2 (en) 2011-08-17 2019-06-04 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US9810495B2 (en) 2011-08-17 2017-11-07 Lwrc International Llc Bolt carrier and bolt for gas operated firearms
US8899138B2 (en) * 2011-09-08 2014-12-02 Adcor Industries, Inc. Firearm having a handle assembly for charging and forward assist
US20130061737A1 (en) * 2011-09-08 2013-03-14 Michael J. Brown Firearm having a handle assembly for charging and forward assist
US20130139424A1 (en) * 2011-12-06 2013-06-06 Benjamin Cory Devine Multi Caliber Quickly Reconfigurable Automatic Machine Gun
US8806789B2 (en) * 2011-12-06 2014-08-19 Benjamin Cory Devine Multi-caliber interchangeable rifle bolt system
US9003686B2 (en) 2012-02-13 2015-04-14 Adcor Industries, Inc. Hand guard mounting mechanism
US8997620B2 (en) 2012-03-09 2015-04-07 Adcor Industries, Inc. Handle assembly for charging a direct gas impingement firearm
US10697726B2 (en) 2012-07-31 2020-06-30 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US11530892B2 (en) 2012-07-31 2022-12-20 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US10808748B2 (en) 2012-07-31 2020-10-20 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US11898589B2 (en) 2012-07-31 2024-02-13 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US10895430B2 (en) 2012-07-31 2021-01-19 Lwrc International Llc Firearm receiver assembly
US10240883B2 (en) 2012-07-31 2019-03-26 Lwrc International Llc Firearm receiver assembly
US11686548B2 (en) 2012-07-31 2023-06-27 Lwrc International Llc Firearm receiver assembly
US9506711B2 (en) 2012-07-31 2016-11-29 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US9772150B2 (en) 2012-07-31 2017-09-26 Lwrc International Llc Firearm receiver assembly
US9816546B2 (en) 2012-07-31 2017-11-14 Lwrc International Llc Barrel nut assembly and method to attach a barrel to a firearm using such assembly
US9625232B2 (en) 2013-03-15 2017-04-18 Lwrc International Llc Firearm buffer system and buttstock assembly
US11460265B2 (en) 2013-03-15 2022-10-04 Lwrc International Llc Firearm buffer system and buttstock assembly
US10591245B2 (en) 2013-03-15 2020-03-17 Lwrc International Llc Firearm buffer system and buttstock assembly
US9915497B2 (en) 2013-03-15 2018-03-13 Lwrc International Llc Firearm buffer system and buttstock assembly
US9506702B2 (en) 2014-01-10 2016-11-29 Jv Precision Machine Company Externally loading semi-automatic firearm with integral or non-removable feeding device
US9719739B2 (en) 2014-02-06 2017-08-01 Bernard (Bernie) T. Windauer Gas block balancing piston for auto-loading firearm
USD759780S1 (en) * 2015-01-20 2016-06-21 Roger Wang Low drag forward assist
DE102017002242A1 (en) 2017-03-07 2018-09-13 Heckler & Koch Gmbh Weapon case and self-loading firearm equipped therewith and a method of making a weapon case
US20180259276A1 (en) * 2017-03-07 2018-09-13 Heckler & Koch Gmbh Automatic firearm housing apparatus and related methods
US11085714B2 (en) * 2017-03-07 2021-08-10 Heckler & Koch Gmbh Automatic firearm housing apparatus and related methods
EP3372943A1 (en) * 2017-03-07 2018-09-12 Heckler & Koch GmbH Weapon housing and self-loading firearm with same and a method for manufacturing a weapon housing

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US20090031606A1 (en) 2009-02-05
US8096074B2 (en) 2012-01-17
US7971382B2 (en) 2011-07-05
US20050262752A1 (en) 2005-12-01
US7971379B2 (en) 2011-07-05
WO2005121686A3 (en) 2008-01-24
US20090007477A1 (en) 2009-01-08
US20090031607A1 (en) 2009-02-05
US7975595B2 (en) 2011-07-12
EP1718914A2 (en) 2006-11-08
WO2005121686A2 (en) 2005-12-22

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