US20030084780A1 - Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons - Google Patents

Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons Download PDF

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Publication number
US20030084780A1
US20030084780A1 US10/010,701 US1070101A US2003084780A1 US 20030084780 A1 US20030084780 A1 US 20030084780A1 US 1070101 A US1070101 A US 1070101A US 2003084780 A1 US2003084780 A1 US 2003084780A1
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United States
Prior art keywords
barrel
firearm
conduits
muzzle jump
recoil
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US10/010,701
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Herbert Rosenthal
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Individual
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Individual
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Priority to US10/010,701 priority Critical patent/US20030084780A1/en
Priority to PCT/US2002/035689 priority patent/WO2003039235A2/en
Priority to US10/353,541 priority patent/US6769346B2/en
Publication of US20030084780A1 publication Critical patent/US20030084780A1/en
Priority to US10/874,514 priority patent/US7377205B2/en
Priority to US11/803,662 priority patent/US7886650B1/en
Abandoned legal-status Critical Current

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    • 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
    • F41A21/28Gas-expansion chambers; Barrels provided with gas-relieving ports
    • 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
    • F41A21/32Muzzle attachments or glands
    • F41A21/36Muzzle attachments or glands for recoil reduction ; Stabilisators; Compensators, e.g. for muzzle climb prevention

Definitions

  • the present invention relates to firearms and weapons, and, more particularly to firearms and weapons adapted to vent gases for reducing muzzle jump and/or recoil action resulting from the act of firing said firearms and weapons.
  • projectile projectile
  • firearms and weapons The firing of projectiles, bullets, shot, and shells (hereinafter “projectile”) from firearms and weapons is an advancement that is well known in the art.
  • the act of firing such firearms and weapons is known to result in recoil and muzzle jump, the reduction of either or both of which is the subject of the present invention.
  • Recoil is the result of a rearward acting force acting upon the weapon, and upon the shooter, during the firing process, which recoil is created by the forward momentum of the projectile.
  • Muzzle jump is an upward movement of the barrel upon firing. Muzzle jump results from the recoil force acting along the longitudinal axis of the barrel, which axis is typically above the point of resistance supporting the weapon.
  • a shoulder-fired weapon such as a rifle or shotgun
  • the highest point on the butt of the weapon namely the heel, is typically one or more inches below the axis of the barrel, and hence below the level at which the recoil force acts.
  • the spacing between the heel and the uppermost exterior portion of the barrel, including what is referred to as the rib is a term of art referred to as the amount of drop at the heel.
  • the recoil force vector acts above the point of resistance thereby resulting in a moment force that causes the barrel to pivot upward.
  • the uppermost portion of the grip or the main bearing portion of the hand upon the rear of the grip is below the level of the barrel. Since the barrel axis represents the recoil force vector, muzzle jump is also experienced with handguns.
  • Recoil and muzzle jump are undesirable for a number of reasons.
  • shooters have been known to flinch, resulting in an uncontrollable momentary closing of the eye, which flinching is a cause of poor aim and missed targets.
  • physically resisting muzzle jump and recoil tends to fatigue the shooter and inhibits the shooter's ability to fire a large number of projectiles, particularly in rapid succession.
  • the reduction of muzzle jump and recoil will enable the use of larger mass projectiles.
  • the recoil force is dependent in part on the weight of the firearm (e.g.
  • recoil reduction increases the shooter's ability to tolerate the firing of larger mass projectiles, than otherwise and/or to use a lighter firearm that otherwise.
  • recoil and muzzle jump each cause the firearm to move out of alignment with the target, follow-up shots at the target are more difficult and the ability of the shooter to rapidly and accurately return the firearm to a properly aimed position is greatly hindered. Accordingly, the reduction of muzzle jump and/or recoil enhances the shooter's ability to rapidly and accurately return the fire arm to a properly aimed position.
  • the reduction of recoil and muzzle jump is also desirable in other applications, such as those applications involving large weapons and/or military cannons.
  • the reduction of recoil shock forces will improve the viability of electronic and mechanical systems and equipment in military hardware such as tanks and ships.
  • the reduction of recoil shock will also benefit the physical and mental well being of personnel in proximity to the firing station associated with large weapons.
  • the reduction of recoil will result in less fatigue and shock stress for metals and other components of the weapon and firing stations, thereby improving durability.
  • U.S. Pat. No. 4,392,413, issued to Gwinn, Jr. discloses a muzzle attachment for a firearm barrel.
  • the muzzle attachment is configured to act as both a muzzle brake to reduce recoil and as a compensator to reduce upward movement of the muzzle when the firearm is fired.
  • U.S. Pat. No. 5,243,895, issued to Dickman et al. discloses a gun barrel defining trapezoidal ports positioned on radials between fifteen and twenty-five degrees from the upper centerline of the barrel to prevent muzzle jump.
  • the present invention provides for adaptation of a projectile firing gun or weapon barrel with a gas porting system having conduits and outlets specifically configured and positioned for maximizing reductions in muzzle jump and/or recoil.
  • the porting system disclosed herein avoids the limitations and disadvantages present in the art by incorporating porting holes located further rearward from the muzzle end of the barrel, which porting holes are in fluid communication with gas conduits terminating in upwardly directed openings for maximizing the generation of thrust forces in a downward direction. Venting explosion gases in a substantially upward direction maximizes downward vector thrust force to counteract muzzle jump. Venting the explosion gases further rearward from the muzzle end of the barrel maximizes the duration of thrust forces as gases are vented well prior to the projectile exiting the barrel.
  • the porting conduits may also be configured with nozzle outlets so as to redirect and concentrate the escaping gases thereby maximizing the forces to counter muzzle jump and/or recoil.
  • a conventional cylindrical gun barrel is adapted with a generally U-shaped body defining a cylindrically concave mid-portion sized for receiving a gun barrel in mating engagement therewith.
  • the gun barrel is adapted to define a pair of left and right side gas venting ports that communicate with generally L-shaped gas conduits defined in the U-shaped body.
  • Each conduit includes an inlet in communication with a corresponding barrel port, and an outlet configured for directing the gases in an upward direction thereby creating a downward force to counter muzzle jump.
  • conduits provide for the diverting or re-directing of a concentrated, high velocity gas stream that results in higher thrust forces than the barrel vent holes disclosed in the art.
  • Another object of the present invention is to provide an improved projectile firing barrel wherein muzzle jump is reduced by venting a concentrated flow of gases and in a substantially vertical direction.
  • Yet another object of the present invention is to provide a system for reducing recoil by venting gases in a rearward direction.
  • Still another object of the present invention is to provide an improved gun or weapon barrel adapted to reduce muzzle jump and/or recoil by routing explosion gases through a conduit flow tube terminating in a nozzle.
  • Another object of the present invention is to provide a system for reducing muzzle jump and/or recoil by tapping the barrel further rearward from the muzzle end of the weapon to utilize and vent gases in closer proximity to firing than venting systems heretofore known in the art.
  • Still another object of the present invention is to provide a system for reducing muzzle jump and/or recoil that requires fewer venting holes than systems disclosed in the background art.
  • Another object of the present invention is to provide a barrel adapted to reduce muzzle jump and/or recoil that is easy to clean and maintain due to fewer venting ports acting to accumulate firing residue.
  • Yet another object of the present invention is to provide a system for reducing muzzle jump and/or recoil that is structured and positioned along the barrel so as to be concealable by the fore-end and thus not to substantially protrude and/or substantially alter the lines of the firearm or weapon.
  • a further object of the present invention is to provide a system for reducing muzzle jump and/or recoil that does not cause the act of firing to be excessively noisy.
  • FIG. 1 is a perspective view of a shotgun having a barrel adapted in accordance with the present invention
  • FIG. 2 is a partial perspective view thereof
  • FIG. 3 is a partial sectional view of FIG. 2;
  • FIG. 4 is a front view thereof in partial section
  • FIG. 5 is a front view in full section of an alternate embodiment
  • FIG. 6 is a front partial view of an alternate embodiment having an outlet defined by a diverging wall
  • FIG. 7 is a front partial view of an alternate embodiment having an outlet defined by a converging wall.
  • FIG. 8 is a partial side view of an alternate embodiment having multiple conduits, one set being configured vertical and the other set being configured approximately 45-degree rearward;
  • FIG. 9 is a partial side view of a shotgun barrel adapted with an approximately 45-degree rearward and upward conduit attachment for reducing muzzle jump and recoil;
  • FIG. 10 is a partial side view of a semi-automatic shotgun barrel adapted with a multiple conduit attachment for reducing muzzle jump and supplying gas to the gas piston;
  • FIG. 11 is a side view of an alternate embodiment adapted for use with a military tank cannon.
  • a preferred embodiment of the present invention includes adapting the barrel of a projectile firing gun or weapon, referenced as 1 , with a gas porting system including a barrel attachment body, generally referenced as 10 .
  • barrel 1 is adapted so as to define vent ports 2 formed by through holes machined in the barrel wall.
  • Barrel attachment 10 is preferably a solid rigid body and defines a pair of gas conduits, referenced as 12 .
  • Conduits 12 each include an inlet 14 in mating relation with a barrel vent port 2 , and outlets or nozzles 16 preferably aligned and vertically disposed relative to the normal, horizontal firing position of the barrel so as to project concentrated explosion gases directly upward thereby maximizing thrust forces to reduce muzzle jump.
  • Attachment body 10 is preferably located further from the muzzle end of the firearm or weapon than systems heretofore known in the art, as best depicted in FIG. 1, so as to initiate the venting of gases sooner after the firing of the weapon or firearm.
  • conduit inlets 14 are sized and positioned for mating engagement with the outer surface of barrel 1 , and particularly so as to be in fluid communication with barrel ports 2 in a manner that forms a pressure resistant seal between the outer surface of the barrel and the engaging surface of body 10 .
  • Attachment body 10 may be fabricated from heat resistant carbon fiber, stainless steel, or any other suitable gunmetal or material.
  • Ports 2 are preferably formed in the lower portion of the barrel since such a configuration is structurally and functionally proven and reliable.
  • the explosion associated with the firing of a weapon generates expanding gases and results in very high pressure within the barrel, which pressure is greater prior to the projectile exiting the barrel. After the projectile exits the barrel the pressure therein rapidly equalizes with atmospheric pressure.
  • the present invention overcomes a number of disadvantages present in the art by locating the porting holes closer toward the receiver end of the barrel so as to take advantage of the high-pressure gases therein well prior to the projectile exiting the barrel. Accordingly, high-pressure gases are vented from the interior of barrel through vent ports 2 , conduits/flow tubes 12 , and outlets or nozzles 16 whereby the pressurized gas is discharged in a concentrated upward direction at a high velocity.
  • the concentrated upwardly escaping gas thus produces a downward (thrust) force that counteracts the tendency of the muzzle to move upward (e.g. muzzle jump). Since conduits 12 and particularly outlets 16 result in discharging the concentrated gas vertically and perpendicular to the barrel axis the downward force is maximized.
  • FIG. 5 depicts an alternate embodiment wherein a single vent port 3 vents gases through conduits 12 and outlets 16 via a T-shaped conduit structure, generally referenced as 18 , defined within body 10 .
  • port 3 is preferably larger than ports 2 shown in FIG. 4 to accommodate a higher volume of gas flow such that the volume of gas flowing through conduits 12 is at least a great as in the preferred embodiment.
  • alternate conduit outlets 18 are defined by a diverging wall to form a diffuser. In such embodiments, the diffuser outlet functions to reduce the velocity of the escaping gas in accordance with principles of fluid dynamics.
  • FIG. 5 depicts an alternate embodiment wherein a single vent port 3 vents gases through conduits 12 and outlets 16 via a T-shaped conduit structure, generally referenced as 18 , defined within body 10 .
  • port 3 is preferably larger than ports 2 shown in FIG. 4 to accommodate a higher volume of gas flow such that the volume of gas flowing through conduits 12 is at least a great as in the preferred embodiment.
  • alternate conduit outlets 18 are defined by a
  • alternate conduit outlets 20 are defined by a converging wall to form a nozzle.
  • the conduit wall may be formed so as to converge over a substantial portion of the conduit length so as to produce a more directed gas stream.
  • the nozzle outlet functions to increase the velocity of the escaping gas in accordance with principles of fluid dynamics.
  • FIGS. 8 - 10 Further alternate embodiments are depicted in FIGS. 8 - 10 .
  • FIG. 8 there is depicted a multiple conduit embodiment wherein the left and right sides of body 10 each define first and second conduits 12 A and 12 B.
  • Conduits 12 A and 12 B each communicate with corresponding barrel vent ports 2 A and 2 B for venting gases through conduit outlets 16 A and 16 B.
  • conduit 12 B is configured vertically upward to divert concentrated gas upward to counteract muzzle jump
  • conduit 12 A is configured at an upward angle so as to divert concentrated gas both upward and rearward to counteract both muzzle jump and recoil. This allows for either a larger downward force or, to the extent that one set of the two conduits is slanted more rearward as depicted in FIG.
  • attachment body 10 includes first and second flow conduits, referenced as 12 A and 12 B.
  • Conduit 12 B is configured to vent concentrated gas, upon firing, in a substantially vertical direction to produce a thrust force for reducing muzzle jump.
  • Conduit 12 A is angled upward and rearward (e.g. toward the shooter), preferably at an angle of approximately 45 degrees to vent concentrated gas, upon firing, upward and rearward to produce a thrust force that has a first thrust force component for reducing muzzle jump and a second thrust force component for reducing recoil.
  • FIG. 10 depicts another alternate embodiment for use with semi-automatic shotguns.
  • attachment body 10 includes first and second flow conduits, referenced as 12 A and 12 B.
  • Conduit 12 B is configured to vent concentrated gas, upon firing, in a substantially vertical direction to produce a thrust force for reducing muzzle jump.
  • Conduit 12 A is configured to route gas to the gas cylinder of the gas operated semi-automatic loading and firing mechanism housed within the weapon.
  • the embodiment depicted in FIG. 10 is mechanically efficient and reliable as compared with alternate systems in the art. Thus, a portion of the gas is used to operate the action and a portion used to produce thrust for reducing muzzle jump.
  • the conduit dedicated to reducing muzzle jump can also act to divert excess gas above that needed to operate the action.
  • FIG. 11 depicts an adaptation of a military weapon barrel, namely, a tank cannon barrel in accordance with the present invention.
  • the cannon barrel is adapted with an attachment body 10 .
  • Attachment body 10 includes first and second flow conduits, referenced as 12 A and 12 B.
  • Conduit 12 A is configured to vent concentrated gas, upon firing, in a substantially vertical direction to produce a thrust force for reducing muzzle jump.
  • Conduit 12 B is configured to vent concentrated gas, upon firing, in a substantially horizontal rearward direction to reduce recoil.
  • concentrated gas may be vented horizontally rearward as shown in FIG. 11 to maximize recoil reducing thrust forces.
  • the present invention further contemplates modifying and/or varying the conduit diameter to maximize the outlet velocity of gases flowing at subsonic as well as supersonic velocities. For example, in the case of subsonic flow a narrowing of the conduit diameter results in an increase in flow velocity. In contrast, however, in the case of supersonic flow an increasing cross section will accelerate the flow.
  • the attachment body of the present invention eliminates the need for a bulky attachment or protuberance affixed to the front of the barrel.
  • the structural alterations may be more fully concealed by the fore-end of the weapon.

Abstract

A projectile firing gun or weapon barrel is adapted with a gas porting system having conduits and outlets specifically configured and positioned for maximizing reductions in muzzle jump and recoil. Principles of reverse thrust are maximized to reduce muzzle jump by incorporating porting holes located toward the butt end of the barrel, which porting holes are in fluid communication with gas conduits terminating in upwardly directed openings for maximizing the generation of downward thrust forces. Venting explosion gases in a substantially upward direction maximizes downward vector thrust force to counteract muzzle jump. Venting the explosion gases at the butt end of the barrel maximizes the duration of thrust forces as gases are vented well prior to the projectile exiting the barrel. The conduits may be configured with nozzle outlets so as to redirect and concentrate the escaping gases thereby maximizing the forces to counter muzzle jump and recoil.

Description

    CROSS REFERENCE TO RELATED APPLICATIONS
  • N/A [0001]
  • STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
  • N/A [0002]
  • COPYRIGHT NOTICE
  • A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or patent disclosure as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all rights whatsoever including copyrights. [0003]
  • BACKGROUND OF THE INVENTION
  • 1. Field of the Invention [0004]
  • The present invention relates to firearms and weapons, and, more particularly to firearms and weapons adapted to vent gases for reducing muzzle jump and/or recoil action resulting from the act of firing said firearms and weapons. [0005]
  • 2. Description of the Background Art [0006]
  • The firing of projectiles, bullets, shot, and shells (hereinafter “projectile”) from firearms and weapons is an advancement that is well known in the art. The act of firing such firearms and weapons is known to result in recoil and muzzle jump, the reduction of either or both of which is the subject of the present invention. Recoil is the result of a rearward acting force acting upon the weapon, and upon the shooter, during the firing process, which recoil is created by the forward momentum of the projectile. Muzzle jump is an upward movement of the barrel upon firing. Muzzle jump results from the recoil force acting along the longitudinal axis of the barrel, which axis is typically above the point of resistance supporting the weapon. For example, a shoulder-fired weapon, such as a rifle or shotgun, has a point of resistance—other than the resistance presented by the weight of the weapon itself—where the butt of the weapon rests against the shooter's shoulder. The highest point on the butt of the weapon, namely the heel, is typically one or more inches below the axis of the barrel, and hence below the level at which the recoil force acts. The spacing between the heel and the uppermost exterior portion of the barrel, including what is referred to as the rib, is a term of art referred to as the amount of drop at the heel. As a result of the drop at the heel, the recoil force vector acts above the point of resistance thereby resulting in a moment force that causes the barrel to pivot upward. Similarly, in the case of a hand-held weapon such as a pistol, the uppermost portion of the grip or the main bearing portion of the hand upon the rear of the grip is below the level of the barrel. Since the barrel axis represents the recoil force vector, muzzle jump is also experienced with handguns. [0007]
  • Recoil and muzzle jump are undesirable for a number of reasons. For example, in anticipation of recoil and muzzle jump shooters have been known to flinch, resulting in an uncontrollable momentary closing of the eye, which flinching is a cause of poor aim and missed targets. Furthermore, physically resisting muzzle jump and recoil tends to fatigue the shooter and inhibits the shooter's ability to fire a large number of projectiles, particularly in rapid succession. In addition, the reduction of muzzle jump and recoil will enable the use of larger mass projectiles. Given that the recoil force is dependent in part on the weight of the firearm (e.g. the heavier the firearm, the lower the resulting recoil experienced by the shooter, and visa versa), and that the use of lighter weight firearms is more desirable for military and police use, as well as any other uses that require one to carry the firearm for long periods of time, recoil reduction increases the shooter's ability to tolerate the firing of larger mass projectiles, than otherwise and/or to use a lighter firearm that otherwise. In addition, since recoil and muzzle jump each cause the firearm to move out of alignment with the target, follow-up shots at the target are more difficult and the ability of the shooter to rapidly and accurately return the firearm to a properly aimed position is greatly hindered. Accordingly, the reduction of muzzle jump and/or recoil enhances the shooter's ability to rapidly and accurately return the fire arm to a properly aimed position. [0008]
  • The reduction of recoil and muzzle jump is also desirable in other applications, such as those applications involving large weapons and/or military cannons. Specifically, the reduction of recoil shock forces will improve the viability of electronic and mechanical systems and equipment in military hardware such as tanks and ships. The reduction of recoil shock will also benefit the physical and mental well being of personnel in proximity to the firing station associated with large weapons. Finally, the reduction of recoil will result in less fatigue and shock stress for metals and other components of the weapon and firing stations, thereby improving durability. [0009]
  • The background art reveals several attempts directed to reducing muzzle jump and recoil. For example, it is known to provide porting for shotgun and firearm barrels to reduce recoil and muzzle jump. The porting of the barrel enables the venting of gases in an upward direction during the firing process. The venting of gases in this manner generates downward forces on the barrel to stabilize the muzzle and reduce muzzle jump. A number of systems attempt to reduce muzzle jump by venting barrel gases at or near the muzzle end of the barrel. For example, U.S. Pat. No. 3,808,943, issued to Kelly, discloses a gun-leveling device that comprises a barrel having trapezoidal slots for venting muzzle gases to prevent muzzle jump. U.S. Pat. No. 4,207,799, issued to Tocco, discloses a muzzle brake for attachment to a handgun for venting gas in a generally upwardly direction to assist in maintaining the firearm stable. U.S. Pat. No. 4,392,413, issued to Gwinn, Jr., discloses a muzzle attachment for a firearm barrel. The muzzle attachment is configured to act as both a muzzle brake to reduce recoil and as a compensator to reduce upward movement of the muzzle when the firearm is fired. U.S. Pat. No. 5,243,895, issued to Dickman et al., discloses a gun barrel defining trapezoidal ports positioned on radials between fifteen and twenty-five degrees from the upper centerline of the barrel to prevent muzzle jump. U.S. Pat. No. 5,587,549, issued to Clouse, discloses a barrel porting system comprising a barrel adapted to define a pair of rows of spaced apart venting orifices extending through the barrel to vent exhaust gases. The venting orifices are configured to vent gases both upwardly and rearwardly, so that resultant vector forces generated by the escaping gases are translated into downwardly and forwardly directed components to reduce muzzle jump and recoil. U.S. Pat. No. 6,269,727, issued to Nigge, discloses a muzzle mounted attachment that deflects combustion gases after leaving the barrel. As noted hereinabove, each of the above-referenced patents disclose systems for venting gases at or near the muzzle end of the barrel. [0010]
  • While the background art reveals a number of attempts directed to reducing muzzle jump and recoil, there remain a number of significant shortcomings with apparatus and methods disclosed. A significant shortcoming involves the effectiveness of muzzle gas venting structures positioned near the muzzle end of the barrel and angularly disposed relative to the upper centerline of the gun barrel. Specifically, the angled vent configuration is less effective at reducing muzzle jump since only a portion of the thrust force generated by the escaping gas is directed in the full vertical direction. Finally, the venting ports disclosed in the background art tend to be located near the muzzle end of the barrel. Accordingly, the venting of muzzle gas occurs relatively late in relation to the firing of the weapon and/or after the projectile has exited the barrel thereby delaying the onset of counteracting forces generated by the escaping gas. In addition, none of the attempts disclose a structure that directs a sufficiency of muzzle gases in a rearward direction for counteracting recoil forces. These and other disadvantages present in the art provide opportunities for substantial improvements and innovation. Thus, there exists a need for improvements in the field of firearms and weapons to reduce muzzle jump and recoil that overcomes the problems and disadvantages present in the background art. [0011]
  • BRIEF SUMMARY OF THE INVENTION
  • The present invention provides for adaptation of a projectile firing gun or weapon barrel with a gas porting system having conduits and outlets specifically configured and positioned for maximizing reductions in muzzle jump and/or recoil. The porting system disclosed herein avoids the limitations and disadvantages present in the art by incorporating porting holes located further rearward from the muzzle end of the barrel, which porting holes are in fluid communication with gas conduits terminating in upwardly directed openings for maximizing the generation of thrust forces in a downward direction. Venting explosion gases in a substantially upward direction maximizes downward vector thrust force to counteract muzzle jump. Venting the explosion gases further rearward from the muzzle end of the barrel maximizes the duration of thrust forces as gases are vented well prior to the projectile exiting the barrel. The porting conduits may also be configured with nozzle outlets so as to redirect and concentrate the escaping gases thereby maximizing the forces to counter muzzle jump and/or recoil. [0012]
  • In a preferred embodiment, a conventional cylindrical gun barrel is adapted with a generally U-shaped body defining a cylindrically concave mid-portion sized for receiving a gun barrel in mating engagement therewith. The gun barrel is adapted to define a pair of left and right side gas venting ports that communicate with generally L-shaped gas conduits defined in the U-shaped body. Each conduit includes an inlet in communication with a corresponding barrel port, and an outlet configured for directing the gases in an upward direction thereby creating a downward force to counter muzzle jump. By attaching the U-shaped body further rearward from the muzzle end of the barrel (i.e. open end from which the projectile exits the barrel) forces are generated sooner, and for longer periods, to counteract muzzle jump and/or recoil. The conduits provide for the diverting or re-directing of a concentrated, high velocity gas stream that results in higher thrust forces than the barrel vent holes disclosed in the art. [0013]
  • Accordingly, it is an object of the present invention to provide a system and method for reducing muzzle jump and recoil in firearms and weapons. [0014]
  • Another object of the present invention is to provide an improved projectile firing barrel wherein muzzle jump is reduced by venting a concentrated flow of gases and in a substantially vertical direction. [0015]
  • Yet another object of the present invention is to provide a system for reducing recoil by venting gases in a rearward direction. [0016]
  • Still another object of the present invention is to provide an improved gun or weapon barrel adapted to reduce muzzle jump and/or recoil by routing explosion gases through a conduit flow tube terminating in a nozzle. [0017]
  • Another object of the present invention is to provide a system for reducing muzzle jump and/or recoil by tapping the barrel further rearward from the muzzle end of the weapon to utilize and vent gases in closer proximity to firing than venting systems heretofore known in the art. [0018]
  • Still another object of the present invention is to provide a system for reducing muzzle jump and/or recoil that requires fewer venting holes than systems disclosed in the background art. [0019]
  • Another object of the present invention is to provide a barrel adapted to reduce muzzle jump and/or recoil that is easy to clean and maintain due to fewer venting ports acting to accumulate firing residue. [0020]
  • Yet another object of the present invention is to provide a system for reducing muzzle jump and/or recoil that is structured and positioned along the barrel so as to be concealable by the fore-end and thus not to substantially protrude and/or substantially alter the lines of the firearm or weapon. [0021]
  • A further object of the present invention is to provide a system for reducing muzzle jump and/or recoil that does not cause the act of firing to be excessively noisy. [0022]
  • Still these and other objects will be disclosed and/or become apparent in view of the detailed description and drawings.[0023]
  • BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
  • FIG. 1 is a perspective view of a shotgun having a barrel adapted in accordance with the present invention; [0024]
  • FIG. 2 is a partial perspective view thereof; [0025]
  • FIG. 3 is a partial sectional view of FIG. 2; [0026]
  • FIG. 4 is a front view thereof in partial section; [0027]
  • FIG. 5 is a front view in full section of an alternate embodiment; [0028]
  • FIG. 6 is a front partial view of an alternate embodiment having an outlet defined by a diverging wall; [0029]
  • FIG. 7 is a front partial view of an alternate embodiment having an outlet defined by a converging wall; and [0030]
  • FIG. 8 is a partial side view of an alternate embodiment having multiple conduits, one set being configured vertical and the other set being configured approximately 45-degree rearward; [0031]
  • FIG. 9 is a partial side view of a shotgun barrel adapted with an approximately 45-degree rearward and upward conduit attachment for reducing muzzle jump and recoil; [0032]
  • FIG. 10 is a partial side view of a semi-automatic shotgun barrel adapted with a multiple conduit attachment for reducing muzzle jump and supplying gas to the gas piston; and [0033]
  • FIG. 11 is a side view of an alternate embodiment adapted for use with a military tank cannon.[0034]
  • DETAILED DESCRIPTION OF THE INVENTION
  • With reference now to the drawings there is depicted an improved porting system for firearm and weapon barrels according to the present invention. As best seen in FIGS. [0035] 1-4, a preferred embodiment of the present invention includes adapting the barrel of a projectile firing gun or weapon, referenced as 1, with a gas porting system including a barrel attachment body, generally referenced as 10. In a preferred embodiment, barrel 1 is adapted so as to define vent ports 2 formed by through holes machined in the barrel wall. Barrel attachment 10 is preferably a solid rigid body and defines a pair of gas conduits, referenced as 12. Conduits 12 each include an inlet 14 in mating relation with a barrel vent port 2, and outlets or nozzles 16 preferably aligned and vertically disposed relative to the normal, horizontal firing position of the barrel so as to project concentrated explosion gases directly upward thereby maximizing thrust forces to reduce muzzle jump.
  • [0036] Attachment body 10 is preferably located further from the muzzle end of the firearm or weapon than systems heretofore known in the art, as best depicted in FIG. 1, so as to initiate the venting of gases sooner after the firing of the weapon or firearm. As should be apparent, conduit inlets 14 are sized and positioned for mating engagement with the outer surface of barrel 1, and particularly so as to be in fluid communication with barrel ports 2 in a manner that forms a pressure resistant seal between the outer surface of the barrel and the engaging surface of body 10. Attachment body 10 may be fabricated from heat resistant carbon fiber, stainless steel, or any other suitable gunmetal or material. Ports 2 are preferably formed in the lower portion of the barrel since such a configuration is structurally and functionally proven and reliable.
  • The explosion associated with the firing of a weapon generates expanding gases and results in very high pressure within the barrel, which pressure is greater prior to the projectile exiting the barrel. After the projectile exits the barrel the pressure therein rapidly equalizes with atmospheric pressure. The present invention overcomes a number of disadvantages present in the art by locating the porting holes closer toward the receiver end of the barrel so as to take advantage of the high-pressure gases therein well prior to the projectile exiting the barrel. Accordingly, high-pressure gases are vented from the interior of barrel through [0037] vent ports 2, conduits/flow tubes 12, and outlets or nozzles 16 whereby the pressurized gas is discharged in a concentrated upward direction at a high velocity. The concentrated upwardly escaping gas thus produces a downward (thrust) force that counteracts the tendency of the muzzle to move upward (e.g. muzzle jump). Since conduits 12 and particularly outlets 16 result in discharging the concentrated gas vertically and perpendicular to the barrel axis the downward force is maximized.
  • FIG. 5 depicts an alternate embodiment wherein a [0038] single vent port 3 vents gases through conduits 12 and outlets 16 via a T-shaped conduit structure, generally referenced as 18, defined within body 10. In the embodiment depicted in FIG. 5, port 3 is preferably larger than ports 2 shown in FIG. 4 to accommodate a higher volume of gas flow such that the volume of gas flowing through conduits 12 is at least a great as in the preferred embodiment. In another alternate embodiment depicted in FIG. 6, alternate conduit outlets 18 are defined by a diverging wall to form a diffuser. In such embodiments, the diffuser outlet functions to reduce the velocity of the escaping gas in accordance with principles of fluid dynamics. In yet another alternate embodiment depicted in FIG. 7, alternate conduit outlets 20 are defined by a converging wall to form a nozzle. The conduit wall may be formed so as to converge over a substantial portion of the conduit length so as to produce a more directed gas stream. In such embodiments, the nozzle outlet functions to increase the velocity of the escaping gas in accordance with principles of fluid dynamics.
  • Further alternate embodiments are depicted in FIGS. [0039] 8-10. With reference to FIG. 8 there is depicted a multiple conduit embodiment wherein the left and right sides of body 10 each define first and second conduits 12A and 12B. Conduits 12A and 12B each communicate with corresponding barrel vent ports 2A and 2B for venting gases through conduit outlets 16A and 16B. In this embodiment, conduit 12B is configured vertically upward to divert concentrated gas upward to counteract muzzle jump, and conduit 12A is configured at an upward angle so as to divert concentrated gas both upward and rearward to counteract both muzzle jump and recoil. This allows for either a larger downward force or, to the extent that one set of the two conduits is slanted more rearward as depicted in FIG. 8, the generation of a forward force to reduce recoil. In the alternate embodiment depicted in FIG. 9 (a partial view) a shotgun barrel is adapted in accordance with the present invention with conduits at such an angle to reduce both muzzle jump and recoil by diverting concentrated gas both upward and rearward. As should be apparent, any variation of the conduit configurations disclosed herein, and various modifications thereof which result in reduction of muzzle jump and/or recoil are considered within the scope of the present invention. With reference to FIG. 8, attachment body 10 includes first and second flow conduits, referenced as 12A and 12B. Conduit 12B is configured to vent concentrated gas, upon firing, in a substantially vertical direction to produce a thrust force for reducing muzzle jump. Conduit 12A is angled upward and rearward (e.g. toward the shooter), preferably at an angle of approximately 45 degrees to vent concentrated gas, upon firing, upward and rearward to produce a thrust force that has a first thrust force component for reducing muzzle jump and a second thrust force component for reducing recoil.
  • FIG. 10 depicts another alternate embodiment for use with semi-automatic shotguns. In the embodiment depicted in FIG. 10 [0040] attachment body 10 includes first and second flow conduits, referenced as 12A and 12B. Conduit 12B is configured to vent concentrated gas, upon firing, in a substantially vertical direction to produce a thrust force for reducing muzzle jump. Conduit 12A is configured to route gas to the gas cylinder of the gas operated semi-automatic loading and firing mechanism housed within the weapon. The embodiment depicted in FIG. 10 is mechanically efficient and reliable as compared with alternate systems in the art. Thus, a portion of the gas is used to operate the action and a portion used to produce thrust for reducing muzzle jump. The conduit dedicated to reducing muzzle jump can also act to divert excess gas above that needed to operate the action.
  • FIG. 11 depicts an adaptation of a military weapon barrel, namely, a tank cannon barrel in accordance with the present invention. As depicted in FIG. 11, the cannon barrel is adapted with an [0041] attachment body 10. Attachment body 10 includes first and second flow conduits, referenced as 12A and 12B. Conduit 12A is configured to vent concentrated gas, upon firing, in a substantially vertical direction to produce a thrust force for reducing muzzle jump. Conduit 12B is configured to vent concentrated gas, upon firing, in a substantially horizontal rearward direction to reduce recoil. In this, and other military embodiments wherein personnel are shielded and or otherwise protected (e.g. ship mounted guns) concentrated gas may be vented horizontally rearward as shown in FIG. 11 to maximize recoil reducing thrust forces.
  • The present invention further contemplates modifying and/or varying the conduit diameter to maximize the outlet velocity of gases flowing at subsonic as well as supersonic velocities. For example, in the case of subsonic flow a narrowing of the conduit diameter results in an increase in flow velocity. In contrast, however, in the case of supersonic flow an increasing cross section will accelerate the flow. [0042]
  • In addition, the attachment body of the present invention eliminates the need for a bulky attachment or protuberance affixed to the front of the barrel. By adapting the barrel with vent ports and an attachment body located at a more rearward location, the structural alterations may be more fully concealed by the fore-end of the weapon. [0043]
  • The instant invention has been shown and described herein in what is considered to be the most practical and preferred embodiment. It is recognized, however, that departures may be made therefrom within the scope of the invention and that obvious modifications will occur to a person skilled in the art. [0044]

Claims (8)

What I claim is:
1. An apparatus for reducing muzzle jump of a firearm or weapon having a barrel section defining a substantially uniform diameter axial bore through which a projectile travels under the influence of expanding gases generated by explosive material, said apparatus comprising:
a barrel defined by a generally cylindrical barrel wall surrounding an axis, said barrel wall defining at least a pair of through bores extending therethrough on opposing lower left and right sides of said barrel for redirecting a portion of the gases produced by the explosive material upon firing of the firearm;
a rigid body attached to an outer portion of said barrel wall, said body having a U-shaped portion for receiving a portion of the barrel therein in mating engagement therewith, said body defining left and right conduits having inlets in corresponding communication with said left and right through bores, each of said conduits having an outlet configured for discharging gases on opposing left and right sides of said barrel in a vertically upward and generally perpendicular direction relative to said barrel axis.
2. An apparatus for reducing muzzle jump of a firearm or weapon according to claim 1, wherein said each of said conduit outlets are defined by diverging conduit walls.
3. An apparatus for reducing muzzle jump of a firearm or weapon according to claim 1, wherein said each of said conduit outlets are defined by converging conduit walls.
4. An apparatus for reducing muzzle jump of a firearm or weapon according to claim 1, wherein said body further defines a second set of left and right conduits in communication with at least one through bore, said second set of left and right conduits each configured to vent gas in a rearward direction for reducing recoil.
5. An apparatus for reducing muzzle jump of a firearm or weapon according to claim 1, further including means for diverting high pressure gas from said barrel to a gas cylinder of said firearm or weapon to actuate gas operated action.
6. An apparatus for reducing muzzle jump of a firearm or weapon having a barrel section defining a substantially uniform diameter axial bore through which a projectile travels under the influence of expanding gases generated by explosive material, said apparatus comprising:
a barrel defined by a generally cylindrical barrel wall formed about an axis, said barrel wall defining at least one through bore extending therethrough for redirecting a portion of the gases produced by the explosive material upon firing of the firearm;
a rigid body attached to an outer portion of said barrel wall, said body having a U-shaped portion for receiving a portion of the barrel therein in mating engagement therewith, said body defining left and right conduits, each of said conduits having an inlet in communication with said at least one through bore, each of said conduits having an outlet configured for discharging gases on opposing left and right sides of said barrel in a vertically upward and generally perpendicular direction relative to said barrel axis.
7. An apparatus for reducing muzzle jump of a firearm or weapon according to claim 6, wherein said each of said conduit outlets are defined by diverging conduit walls.
8. An apparatus for reducing muzzle jump of a firearm or weapon according to claim 6, wherein said each of said conduit outlets are defined by converging conduit walls.
US10/010,701 2001-11-08 2001-11-08 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons Abandoned US20030084780A1 (en)

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Application Number Priority Date Filing Date Title
US10/010,701 US20030084780A1 (en) 2001-11-08 2001-11-08 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons
PCT/US2002/035689 WO2003039235A2 (en) 2001-11-08 2002-11-06 Conduits and nozzles for reduction muzzle jump
US10/353,541 US6769346B2 (en) 2001-11-08 2003-01-29 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons
US10/874,514 US7377205B2 (en) 2001-11-08 2004-06-23 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons
US11/803,662 US7886650B1 (en) 2001-11-08 2007-05-15 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons

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US10/010,701 US20030084780A1 (en) 2001-11-08 2001-11-08 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons

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US10/353,541 Expired - Fee Related US6769346B2 (en) 2001-11-08 2003-01-29 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons
US10/874,514 Expired - Fee Related US7377205B2 (en) 2001-11-08 2004-06-23 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons

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US10/874,514 Expired - Fee Related US7377205B2 (en) 2001-11-08 2004-06-23 Reverse thrust system with integral conduits and nozzles for the reduction of muzzle jump and/or recoil in firearms and weapons

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US20150226503A1 (en) * 2012-08-06 2015-08-13 Ata Silah San. A.S. Novel operating system in the semi-automatic firearms
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Also Published As

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US7377205B2 (en) 2008-05-27
WO2003039235A2 (en) 2003-05-15
WO2003039235A3 (en) 2004-02-12
US6769346B2 (en) 2004-08-03
US20030136251A1 (en) 2003-07-24
US20050066803A1 (en) 2005-03-31

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