Firearm box magazine with straight end and intermediate arcuate portions

April 29, 1969 r. d. fremont 3,440,751

FIREARM BOX MAGAZINE WITH STRAIGHT END AND INTERMEDIATE ARCUATE PORTIONS

Filed June 30, 1967

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ATTORNEYS

3,440,751

Patented Apr. 29, 1969

United States Patent Office

3,440,751

FIREARM BOX MAGAZINE WITH STRAIGHT END AND INTERMEDIATE ARCUATE PORTIONS

Robert D. Fremont, Farmington, Conn., assignor to Colt’s Inc., Hartford, Conn., a corporation of Arizona Filed June 30, 1967, Ser. No. 650,275

Int. Cl. F41c 25/02

U.S. Cl. 42—50 3 Claims

ABSTRACT OF THE DISCLOSURE

A small arms, magazine having increased ammunition capacity and employing straight end and intermediate arcuate portions conducive to ready loading and feedout of tapered cartridges, and ready insertion of the magazine into a firearms magazine housing. A spring driven follower includes a depending post which bottoms against the lower end of the magazine.

This invention pertains to firearms ammunition magazines and more particularly to an improved small arms magazine having increased ammunition capacity.

The typical round of high velocity combat ammunition includes a cartridge which presents a tapered configuration. Accommodation of such cartridges in magazines of capacity greater than those now commonly used presents difficulties which this invention resolves.

It is an object of this invention to provide a new, improved and increased capacity small arms magazine to reduce resupply needs and enhance weapons utilization, particularly in the field.

An additional object of the invention is to provide a new and improved small arms magazine having increased ammunition capacity and which combines the increased capacity with facile loading and reliable and smooth subsequent feedout of tapered cartridges.

An additional object of this invention is to provide a new, improved and increased capacity small arms magazine that accommodates stacks of tapered cartridges forming a fan shape and prevents bottoming of the follower.

An additional object of this invention is to provide a new, improved and increased capacity firearms magazine which combines smoothly merging curved and linear wall construction to accommodate the fan-like spread of stacked, tapered cartridges.

Other objects and advantages of this invention become apparent in the specifications and claims below.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application which will be indicated in the appended claims.

In the drawings:

FIG. 1 is a side elevation, partly broken away, of a magazine embodying the present invention;

FIG. 2 is a front elevation, partly broken away, of the magazine illustrated in FIG. 1 and showing several cartridges in place therein; and

FIG. 3 is a perspective view of the lip and magazine housing segment and follower of the magazine illustrated in FIG. 1.

Now having detailed reference to the drawings, a thirty round embodiment of a magazine 10 utilizing my invention is shown. A suitable base plate 23 closes the magazine at its lower end and supports a spiral follower spring 24 terminating at both ends in line with the raised portion 26 of the somewhat cartridge-like follower 25 as shown, and which follower engages the two bottommost of the cartridges stacked in staggered relation within the magazine. The follower is appropriately tiltably joined to the spring 24, and the usual friction reducing corrugations are provided in the sidewalls 15 as shown.

The sidewalls 15 and front and rear end walls 16 and 17 respectively, of the magazine 10 include an upper ⁵ portion 18 which comprises the lip segment 19 and a straight-side box segment 20 adapted for ready insertion a substantial distance into the magazine housing of a firearm’s receiver.

Sidewalls 15 and end walls 16 and 17 of magazine 10 extend from the box segment 20 in curved fashion and form a fan-like or arcuate body portion 21 having its upper termination at A and positioned near the midpoint of the total magazine length. The curve describes, 15 preferably, a uniform arc of about 18° measured between the radii A and B of FIG. 1.

From the lower termination or radius B of the arcuate portion 21, the sidewalls 15 and end walls 16, 17 extend linearly to form the bottom and straight body portion 20 22 of the magazine 10, maintaining the compact and smooth contour introduced by the arcuate portion. 21 which will be seen to interconnect the straight terminal body portions 18 and 22 to constitute a significantly improved magazine body. The utilization of this arcuate 25 portion ensures that the magazine will accommodate the non-linear and fan spread of tapered cartridges stacked higher than heretofore.

Tiltability of the follower 25 relatively to the follower spring 24 also serves to accommodate the fan build-up 30 of tapered cartridges in the straight-side portions 20 and 22. .

Use of an arcuate center portion such as 21 accommodates the installation of base plate 23 perpendicularly relatively to the end walls 16 and 17.

The terminations 27 and 28 of the spring 24 rearwardly of the centerline of the spring 24 and thus under the cartridge contacting raised portion 26 of the follower 25 provide additional spring force thereunder, ensuring continuous smooth cartridge feed. .

A follower stop post 29 is shown disposed rearwardly of the center of the spring 24 viewed side to side across the magazine and centrally of the center of the spring viewed front to rear of the same. Also as shown, the post may be tapered, truncated and cross-sectionally 45 elliptical element sufficiently long to effect positive stopping of the follower before there is follower spring coil to coil contact. ... _A

The magazine of the invention thus provides increased capacity for tapered ammunition in a compact configura50 tion that ensures ready mating of the magazine with the magazine housing of an associated firearm designed to accommodate a straight magazine of necessarily limited capacity, and reliable cartridge feeding during use.