US2736117A - Firearm with aluminum barrel and receiver - Google Patents

Firearm with aluminum barrel and receiver Download PDF

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US2736117A
US2736117A US2736117DA US2736117A US 2736117 A US2736117 A US 2736117A US 2736117D A US2736117D A US 2736117DA US 2736117 A US2736117 A US 2736117A
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receiver
chamber
liner
barrel
member
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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
    • F41A21/48Barrel mounting means, e.g. releasable mountings for replaceable barrels
    • F41A21/481Barrel mounting means, e.g. releasable mountings for replaceable barrels using partial or interrupted threads, e.g. bayonet-type mountings
    • 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
    • F41A21/00Barrels; Gun tubes; Muzzle attachments; Barrel mounting means
    • F41A21/12Cartridge chambers; Chamber liners
    • 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
    • F41A21/20Barrels or gun tubes characterised by the material

Description

Feb. 28. 1956 R. E. CLARKSON ET AL 2,736,117

FIREARM WITH ALUMINUM BARREL AND RECEIVER 2 Sheets-Sheet 1 Filed Dec. 18 1951 Feb. 28, 1956 R. E. CLARKSON ET AL 2,736,117

FIREARM WITH ALUMINUM BARREL AND RECEIVER Filed Dec. 18, 1951 2 Sheets-Sheet 2 ijnited States Patent Ofiice 2,736,117 Patented Feb. 23, 1956 FIREARM WITH ALUMINUM BARREL AND RECEIVER Ralph E. Clarkson, Hamden, and Tuines W. van Wilgen, Branford, Conn., assignors to Olin Mathieson Chemical Corporation, a corporation of Virginia Application December 18, 1951, Serial No. 262,281

Claims. (CI. 42-75) This invention relates to firearms, and particularly to repeating or semi-automatic shotguns, and has for its object the provision of improvements in the receiver and in the barrel connection to the receiver to effect a reduction in weight without sacrificing strength. Our invention provides a means, which, for convenience, we shall refer to as the liner-chamber, comprising an improved chamber member with means for connecting the barrel thereto, and a receiver liner integral with the chamber member for insertion into the receiver.

In a preferred embodiment, the liner-chamber is a unitary structure with means for the removable connection of the barrel to the chamber member and for locking the breech block to the receiver liner. On important feature of the invention is the provision of a shoulder, such as an annular shoulder, on the unitary liner-chamber against which the receiver extension abuts and can, therefore, always be secured in exact operative position with respect to the chamber member.

The invention provides a combination of the receiver liner of any suitable construction, the receiver liner being constructed and arranged to receive the impact of the explosion on the breech block, thus permitting the use of a receiver constructed of lightweight or low strength materials. The invention also provides a combination of the liner-chamber with a barrel of any suitable type, and the barrel may be connected to the chamber member in any manner, advantageously by half-threads to facilitate rapid connection and removal. The unitary construction of the liner-chamber provides a rigid, strong connection between the breech block and the chamber member, and the chamber member is advantageously constructed to receive the major force of the explosion. We are, therefore, able to use relatively very lightweight barrels, such as those made of very thin steel or aluminum alloys, thus effecting a material reduction in the weight of the gun. V

The invention is advantageously applicable to firearms having a breech block with locking means engageable with a shoulder in the receiver. One of the important advantages of the invention is that the breech block locking shoulder is in the receiver liner and the breech block may be mounted in the receiver liner and fitted for head-spacing prior to mounting in the receiver or attaching to the barrel. The unitary construction provides fixed dimensions between the breech block locking shoulder and the chamber. An advantage in this construction is that in using the liner-chamber of the invention in such receivers as that of the model 12 Winchester shotgun the difficult head-spacing is materially simplified.

Although the invention is advantageously applicable to various types of repeating or semi-automatic firearms, for the purpose of illustration the unitary liner-chamber in combination with a receiver and with a barrel will be shown and described in connection with the model 12 Winchester repeating shotgun.

These and other novel features of the invention will be better understood after considering the following discussion taken in conjunction with the a ccompanying drawings, in which:

Fig. 1 is a side view of the major portion of a model 12 Winchester repeating shotgun;

Fig. 2 is an enlarged fragmentary view, partly in section, of the shotgun of Fig. l with parts removed;

Fig. 3 is an exploded fragmentary side view of the liner-chamber and barrel, partly in section;

Figs. 4 and 5 are sectional views at 3-4 and 5-5, respectively, of Fig. 2;

Fig. 6 is an enlarged fragmentary sectional view, partly in section, at 6 of Fig. 2;

Fig. 7 is a perspective of the receiver extension;

Fig. 8 is a perspective from the forward end of a linerchamber of the invention, and

Fig. 9 is a perspective of the barrel from the chamber end.

The model 12 shotgun illustrated in the drawings comprises a receiver 1, a breech block 2, barrel 3, receiver extension 4, magazine tube 5, and action slide handle 6. The details of the action and firing mechanism are omitted from the description as they are well known and unnecessary in understanding the invention. Any suitable devices of that character may be used depending upon the type of gun in which the invention is used. As best shown in Figs. 2, 3 and 6, the liner-chamber 7 is a unitary structure formed, for example, of high strength alloy steel, beryllium bronze, and the like, and comprises as principal parts the chamber member 8, the receiver liner 9, and an annular rib 10. The receiver liner 9 is suitably cut out or fashioned for receiving the particular breech block used for blocking the breech and to provide opening means for loading shells into the chamber and ejecting the cases after firing. The receiver liner, in its broader aspects, is a rigid extension of the chamber member for effecting a secure and preferably detachable connection to the receiver, and also to effect a locking connection with the breech block. While the unitary construction is most advantageous and preferred for most purposes, we may construct the receiver liner and chamber member as separate parts and connect them into an integral structure, as by threads or welding. Hereinafter, when we refer to an integral liner-chamber, we include one formed of two connected parts or a unitary structure. The linerchamber has a threaded section 15 by means of which the entire structure 7 is securely attached to the receiver 1, including locking shoulder 16 for the breech block. In its assembled position in the gun, the annular rib 10 is brought into tight contact with the receiver end-surface 17, thus providing a definite fixed space between the chamber member and the means in the receiver (not shown) for operating the breech block. Moreover, the unitary structure prior to installation, as shown in Fig. 8, can be fitted to its breech block for head-spacing very advantageously as the shoulder 16' is easily accessible for any trimming that may be necessary.

The chamber member comprises an inner bore 18 which is the actualshell chamber, a relatively thick wall portion 19 and a necked forward end portion 20 surrounding the bore 18, and the two half thread sections 21 and 22 on the Wall portion. The necked portion 20 may be relatively thin at its extreme edges, say, from 0.030 to 0.040 inch thick, and in a fairly snug contact with the barrel so that the neck can expand within its elastic limits into sealing contact with the barrel. We may select a material for the chamber member having a modulus of elasticity which, in comparison with the modulus of elasticity of the barrel, will effect good sealing contact on expansion. The unitary linear-chamber when mounted in the receiver, as shown at the left Fig. 3, has the rigid chamber member 8 projecting forward.

As a point of interest illustrative of the construction and function of the liner-chamber, a shell could be inserted into the chamber member, the breech block locked in the receiver liner, and the liner-chamber held by any securing structure, such as a vise, and fired because the receiver liner is the essential loading-carrying medium. We may, accordingly, form the receiver of plastic material, any light metal such as aluminum, steel stampings, or malleable iron castings. We may also use any high strength molded or laminated material, such as bonded glass fibers, which have dampening characteristics. The barrel may be made of a very thin strong metal such as steel, or of a light metal such as aluminum. We prefer to use a high strength aluminum alloy rod or bar stock formed of alloys such as 14S-T, 17S-T, 75S-T, 24S-T, 24S-RT, and R303-T, and we may treat the aluminum, especially for the barrel, according to any suitable anodizing process. The barrel may be formed of a high strength alloy such as 75S-T which has a cladding of relatively pure aluminum either inside or outside to reduce shattering of the less ductile 75S-T. The barrel is coupled by means of half-threads (with or without pitch) directly to the complementary half-threads 21 and 22 of the chamber member or by other suitable means.

In the embodiment illustrated, the receiver extension 4 is used to eifect a very practicable connection of the barrel, magazine tube and slide handle for quick takedown purposes. The receiver extension 4 has interior threads 25 for engaging the exterior threads 26 on the barrel. When the receiver extension is screwed into position on the barrel with the face 27 in tight engagement with the shoulder 28 of the barrel, the opposite face 29 of the receiver extension is in close contact with the forward face of the annular rib 10. The receiver extension has a tubular extension 32 in which the magazine tube is in slidable connection. The magazine tube has halfsection lugs 33 and 34 for engaging complementary halfsection lugs in the receiver, as shown in Fig. 2, which hold the receiver extension on the receiver in a nonturnable position.

In disconnecting the barrel, receiver extension, and magazine, the locking pin 35 is disengaged, the magazine tube is given a quarter turn and is pulled forward out of its threaded recess in the receiver. The barrel, magazine, and receiver extension can then be given a one-quarter turn to disengage the half-threads 21 and 22 and the barrel can be slipped off the chamber member.

We claim:

1. A liner-chamber for firearms comprising in integral connection a chamber member having means for removably connecting a barrel thereto in fixed operative position i and a receiver liner having means for attaching to the receiver of a gun in a fixed operative position and for the operation of a breech block therewith, said chamber member having a wall portion which will contain the force of an explosion therein, and a necked portion at its forward end that is expansible intocontact with a surrounding barrel at the time of explosion, said chamber wall portion being appreciably thicker than the necked portion.

2. A liner-chamber according to claim 1 comprising threads on the chamber member for the connection of a barrel thereto and threads on the receiver liner for connection to a receiver.

3. A liner-chamber according to claim 1 comprising a rib for effecting abutting engagement with the receiver.

4. A liner-chamber according to claim 1 which comprises half-threads on the exterior of the chamber member for the removable attachment of the barrel thereto.

5. The combination in shotguns which comprises a receiver, an integral liner-chamber comprising a chamber member and a receiver liner, thread means for mounting the receiver liner in a fixed position in the receiver with the chamber member extending forwardly beyond the receiver, means on the chamber member for securing a barrel in an operative immovable position over the chamber, said chamber member having a Wall section capable of containing the force of an explosion therein and a necked wall section at its forward end that is expansible into a sealing contact with the surrounding barrel at the time of explosion, said first-mentioned wall section being appreciably thicker than the necked wall section.

6. The combination according to claim 5 which comprises an annular rib on the liner-chamber that effects abutting engagement with the receiver, a receiver extension in threaded connection with the exterior end portion of the barrel, threads on the exterior of the chamber member for screwing the barrel thereon until the receiver extension makes abutting contact with the annular rib.

7. The combination according to claim 5 in which the barrel is formed of aluminum and the liner-chamber is formed of steel.

8. The combination according to claim 5 in which the receiver is formed of aluminum and the liner-chamber is formed of steel.

9. The combination in shotguns which comprises an aluminum receiver, a unitary liner-chamber having a receiver liner and a chamber liner, the receiver liner having a breech block and locking means therefor and being in threaded connection with the receiver, a rib on the linerchamber located at the junction of the receiver liner and the chamber liner, exterior threads on the receiver liner and on the chamber liner, said receiver liner being threaded into the receiver, an aluminum barrel having interior threads in threaded connection with the chamber liner which is inserted into the barrel, said rib being in abutting engagement with thereceiver and the barrel being in abutting engagement with the rib, said chamber liner having sufficient structural strength to contain the pressure of the explosion independently of the barrel.

10. The combination in shotguns which comprises an aluminum receiver, a unitary liner-chamber having a receiver liner in fixed operative connection to the receiver and a chamber liner for insertion into a barrel with removable connection thereto, said connections being in juxtaposition on the exterior of said unitary liner-chamber, breech block locking means on the receiver liner, a breech block in operative engagement in the receiver liner, said connecting means effecting a fixed relation between the receiver, liner-chamber and barrel, and an aluminum barrel in said removable but operatively fixed connection with the chamber member, at least a portion of the chamber liner extending into the barrel being expansible into contact with the barrel at the time of explosion, whereby the force of the explosion on the breech block is absorbed by the receiver liner and the major pressure of the explosion is contained by the chamber member.

References Cited in the file of this patent UNITED STATES PATENTS 781,765 Browning Feb. 7, 1905 1,234,783 Mauser July 31, 1917 1,628,798 -Nelson May 17, 1927 1,864,374 Romberg et al. June 21, 1932 2,440,634 Henney Apr. 27, 1948 2,476,232 Williams July 12, 1949 FOREIGN PATENTS 831,030 France May 30, 1938 OTHER REFERENCES Stoegers Catalog, The Shooters Bible, 1940 ed., page 111.

US2736117A 1951-12-18 Firearm with aluminum barrel and receiver Expired - Lifetime US2736117A (en)

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DE (1) DE952506C (en)
FR (1) FR1067402A (en)
GB (1) GB702448A (en)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2845741A (en) * 1955-04-27 1958-08-05 Olin Mathieson Composite firearm barrel
US2847786A (en) * 1955-02-07 1958-08-19 Olin Mathieson Composite firearm barrel comprising glass fibers
US2898693A (en) * 1956-04-17 1959-08-11 Sturm Ruger & Co 22 caliber conversion for a colt 45 caliber semi-automatic pistol
US2935913A (en) * 1956-04-24 1960-05-10 Olin Mathieson Gun barrel
US2952089A (en) * 1957-01-16 1960-09-13 Olin Mathieson Chamber structure for guns
US3023527A (en) * 1958-12-15 1962-03-06 Remington Arms Co Inc Firearm having receiver bearing surfaces of synthetic resinous material
US4454672A (en) * 1981-02-13 1984-06-19 Jali Timari Lock means
US5412895A (en) * 1993-03-09 1995-05-09 Krieger; John M. Floating gun barrel mount
US5740516A (en) * 1996-12-31 1998-04-14 Remington Arms Company, Inc. Firearm bolt
WO1998050753A1 (en) * 1997-05-06 1998-11-12 Tor Heen Devices to enable flexible replacing of gun barrels
US7076904B1 (en) * 2002-06-06 2006-07-18 Rustick Joseph M Detachable gun barrel assembly
US7107715B2 (en) 2003-05-23 2006-09-19 Ra Brands, L.L.C. Bolt assembly with locking system
US20100154268A1 (en) * 2003-08-15 2010-06-24 Juan Francisco Mautone Medvedeo Semi-automatic weapon for several tubes cartridges loading system for long guns
US20100186581A1 (en) * 2003-12-03 2010-07-29 Snake River Machine, Inc. Method and apparatus for an action system for a firearm
US20120090588A1 (en) * 2010-10-14 2012-04-19 Jeffrey Chen Initial velocity accelerating tube
US20140000142A1 (en) * 2012-07-02 2014-01-02 Swetal K. Patel High Strength Upper Receiver System and Method for Modular Rifle
US20150135575A1 (en) * 2013-11-21 2015-05-21 Thomas G. Wood, JR. Firearm accessory mounting assembly
US20160298918A1 (en) * 2015-04-08 2016-10-13 Ra Brands, L.L.C. Shotgun with Magazine Loading System

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE516196A (en) * 1951-12-18
DE1203161B (en) * 1957-04-20 1965-10-14 George Curry Sullivan Firearm

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US781765A (en) * 1903-07-10 1905-02-07 John M Browning Magazine-gun.
US1234783A (en) * 1914-12-01 1917-07-31 Waffenfabrik Mauser Ag Means for combining the barrel with the receiver in connection with firearms.
US1628798A (en) * 1921-02-04 1927-05-17 Savage Arms Corp Firearm
US1864374A (en) * 1931-01-09 1932-06-21 Rheinische Metallw & Maschf Firearm
FR831030A (en) * 1937-04-01 1938-08-18 Canon for guns or other weapons
US2440634A (en) * 1943-10-14 1948-04-27 Gen Motors Corp Shell feeding mechanism for rocket guns
US2476232A (en) * 1947-11-06 1949-07-12 Olin Ind Inc Inertia operated bolt lock

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE641356C (en) * 1931-04-19 1937-01-28 Siemens Ag Padlock for firearms
US2447091A (en) * 1943-09-18 1948-08-17 Arthur J Pope Interchangeable gun barrel and stock
US2511505A (en) * 1948-12-07 1950-06-13 Norman A Hemmerling Magazine plug for repeating shotguns

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US781765A (en) * 1903-07-10 1905-02-07 John M Browning Magazine-gun.
US1234783A (en) * 1914-12-01 1917-07-31 Waffenfabrik Mauser Ag Means for combining the barrel with the receiver in connection with firearms.
US1628798A (en) * 1921-02-04 1927-05-17 Savage Arms Corp Firearm
US1864374A (en) * 1931-01-09 1932-06-21 Rheinische Metallw & Maschf Firearm
FR831030A (en) * 1937-04-01 1938-08-18 Canon for guns or other weapons
US2440634A (en) * 1943-10-14 1948-04-27 Gen Motors Corp Shell feeding mechanism for rocket guns
US2476232A (en) * 1947-11-06 1949-07-12 Olin Ind Inc Inertia operated bolt lock

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2847786A (en) * 1955-02-07 1958-08-19 Olin Mathieson Composite firearm barrel comprising glass fibers
US2845741A (en) * 1955-04-27 1958-08-05 Olin Mathieson Composite firearm barrel
US2898693A (en) * 1956-04-17 1959-08-11 Sturm Ruger & Co 22 caliber conversion for a colt 45 caliber semi-automatic pistol
US2935913A (en) * 1956-04-24 1960-05-10 Olin Mathieson Gun barrel
US2952089A (en) * 1957-01-16 1960-09-13 Olin Mathieson Chamber structure for guns
US3023527A (en) * 1958-12-15 1962-03-06 Remington Arms Co Inc Firearm having receiver bearing surfaces of synthetic resinous material
US4454672A (en) * 1981-02-13 1984-06-19 Jali Timari Lock means
US5412895A (en) * 1993-03-09 1995-05-09 Krieger; John M. Floating gun barrel mount
US5740516A (en) * 1996-12-31 1998-04-14 Remington Arms Company, Inc. Firearm bolt
WO1998050753A1 (en) * 1997-05-06 1998-11-12 Tor Heen Devices to enable flexible replacing of gun barrels
US7076904B1 (en) * 2002-06-06 2006-07-18 Rustick Joseph M Detachable gun barrel assembly
US7107715B2 (en) 2003-05-23 2006-09-19 Ra Brands, L.L.C. Bolt assembly with locking system
US7219461B1 (en) 2003-05-23 2007-05-22 Ra Brands, L.L.C. Bolt assembly with locking system
US20070107290A1 (en) * 2003-05-23 2007-05-17 Ra Brands, L.L.C. Bolt assembly with locking system
US20100154268A1 (en) * 2003-08-15 2010-06-24 Juan Francisco Mautone Medvedeo Semi-automatic weapon for several tubes cartridges loading system for long guns
US7752795B1 (en) * 2003-08-15 2010-07-13 Juan Francisco Mautone Medvedeo Semi-automatic weapon for several tubes cartridges loading system for long guns
US20100186581A1 (en) * 2003-12-03 2010-07-29 Snake River Machine, Inc. Method and apparatus for an action system for a firearm
US7770507B1 (en) * 2003-12-03 2010-08-10 Snake River Machine, Inc. Method and apparatus for an action system for a firearm
US20120090588A1 (en) * 2010-10-14 2012-04-19 Jeffrey Chen Initial velocity accelerating tube
US8453634B2 (en) * 2010-10-14 2013-06-04 J.B. Unicorn Ltd. Initial velocity accelerating tube
US20140000142A1 (en) * 2012-07-02 2014-01-02 Swetal K. Patel High Strength Upper Receiver System and Method for Modular Rifle
US8739449B2 (en) * 2012-07-02 2014-06-03 Swetal K. Patel High strength upper receiver system and method for modular rifle
US20150135575A1 (en) * 2013-11-21 2015-05-21 Thomas G. Wood, JR. Firearm accessory mounting assembly
US9261318B2 (en) * 2013-11-21 2016-02-16 Thomas G Wood, Jr. Firearm accessory mounting assembly
US20160298918A1 (en) * 2015-04-08 2016-10-13 Ra Brands, L.L.C. Shotgun with Magazine Loading System

Also Published As

Publication number Publication date Type
DE952506C (en) 1956-11-15 grant
FR1067402A (en) 1954-06-15 grant
GB702448A (en) 1954-01-13 application
BE516115A (en) grant

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