US3054206A

US3054206A - Means for retaining magazine-fed firearm cartridges in bolt pickup position

Info

Publication number: US3054206A
Application number: US82660A
Authority: US
Inventors: Edmond J Raleigh
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-01-13
Filing date: 1961-01-13
Publication date: 1962-09-18
Anticipated expiration: 1979-09-18

Description

IN VEN TOR EdmnndIRn'lei h E. J. RALEIGH MEANS FOR RETAINING MAGAZINE-FED FIREARM CARTRIDGES IN BOLT PICKUP POSITION Filed Jan. 15, 1961 Wa -ma W Sept. 18, 1962 United States Patent Ofllice 3,054,206 Patented Sept. 18, 1962 Secretary of the Army Filed Jan. 13, 1961, Ser. No. 82,660 4 Claims. (Cl. 42-18) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.

This invention relates to magazine fed firearms with reciprocating bolts and more particularly to devices for supporting the top cartridges in a magazine so as to assure positive pickup by the bolt and to bufler devices for resiliently stopping the bolt in the recoil position thereof and energizing the bolt for counterrecoil flight.

With those firearms which fire at a rapid rate and have a reciprocating bolt which transfers a cartridge from a magazine to the barrel chamber when traveling from the recoil to the battery position, a nonfiring condition oftentimes develops through the leading cartridge in the magazine being below the path of travel of the bolt when passing thereby. This condition is caused by the surge produced in the magazine spring, as it functions to move the cartridges in the magazine upwardly therein when the leading cartridges are successively removed by the bolt, and the rapid rate of fire which does not permit time for the surging to subside in the spring between the cyclic functions thereof.

It is, therefore, an object of this invention to provide a retainer device which supports the leading cartridge in a magazine to assure pickup by the bolt.

It is another object of this invention to provide such a retainer device which is actuated by the bolt.

It is a further object of this invention to provide such a retainer device which also serves as a buffer for the bolt.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing in which:

FIG. 1 is a longitudinally cross-sectioned view of a firearm receiver showing the bolt disposed between the battery and recoil position thereof and the leading cartridge in the magazine engaged with the underside of the retainer;

FIG. 2 is a fragmentary view similar to FIG. 1 but showing the bolt stopped in the recoil position by the buffer-retainer and the leading cartridge in the magazine released by the retainer for displacement to the position for pickup by the bolt;

FIG. 3 is a view similar to FIG. 2 but showing the buffer-retainer forwardly displaced to extend the forward end thereof into engagement with the pickup position cartridge for support thereof and the bolt energized for counterrecoil flight;

FIG. 4 is a view taken along line 4'4 of FIG. 3; and

FIG. 5 is an enlarged view of the butter-retainer.

Shown in the figures is a firearm receiver 12 in which a cylindrical bolt 14 is slidingly received by a channel 16 for longitudinal reciprocation in recoil and counterrecoil strokes to and from a recoil position. Receiver 12 is provided with a vertically disposed well 18 which extends therethrough to channel 16 and which is adapted to receive a cartridge magazine 20. Magazine 20 is of double-stacked type wherein a plurality of stored cartridges 22 are moved alternately and in contact relationship from the two stacks to a central neck 24 for successive removal by bolt 14 during the counterrecoil strokes thereof. The remaining cartridges 22 in magazine 20 are forced by a spring 26 therein towards neck 24 as the leading cartridge therein is removed by bolt 14.

Provided in receiver 12 is a chamber section 32 of rectangular cross-section, which extends rearwardly into receiver 12 from the rear end of well 18 and which is open at the top to channel 16. Chamber section 32 is terminated at the rear end by a wall 34 which extends vertically upward to channel 16. A bore 36 extends longitudinally rearward from wall 34 to a bottom 37 and receives a compressible coil spring 38 for contact therewith.

A buffer-retainer 40 includes a cylindrical shaft 42, which is slidingly received by bore 36 forwardly of spring 38, and an integral plate 44 laterally disposed on the front end of the shaft. Plate 44 has a rectangular cross-section of approximately the same dimensions as those of chamber section 32 so that the plate is slidingly received thereby. The top of plate 44 extends upwardly into channel 16 and is provided with an arcuate, mating relief 45 for bolt 14.

The free end of shaft 42 contacts the front end of spring 3% to bias buffer-retainer 4t} forwardly. The forward displacement of buffer-retainer 44) is limited by the contact of a stop 46 extending radially from shaft 42 with the front end of a slot 48 extending upwardly from bore 36 to channel 16. The rearward displacement of buffer-retainer 413 is limited by the contact of plate 44 with wall 34.

Extending forwardly from plate 44 is a pair of laterally spaced tines 5'0 which, when buffer-retainer 40 is rearwardly displaced, are retracted within chamber section 32. When buffer-retainer 4-0 is forwardly displaced, tines 5d extend through an opening 51 in the rear side of magazine 2i) for engagement with the underside of the base of cartridge 22 in neck 24. Tines 50 are spaced apart a distance slightly less than the diameter of the base of cartridge 22 and are vertically positioned so as to be insertable into the clearances on opposite sides of the area of contact between the leading cartridge in neck 24 and the next succeeding cartridge when the leading cartridge is positioned for pickup by bolt 14. By tines 5% being so spaced apart the succeeding cartridge 22 in magazine 24 is displaceable a portion of the pitch of movement of the cartridges in neck 24 when the leading cartridge is removed therefrom. Whereby, such succeeding cartridge 22, now the leading cartridge, has to be displaced only slightly more than a half-pitch when released, as hereinafter described, by butterretainer 40 to the position in neck 24 for pickup by bolt 14.

Provided on the front portion of each of the tines 50 is a spiral ramp 52 which extends rearwardly and upwardly from the front end thereof. Ramps 52 assure the engagement of the base of the leading cartridge 22 in neck 24 by tines 50 when buffer-retainer 40 is forwardly displaced. Tines 50 are disposed so that, when extended under the base of the leading cartridge 22, the base is raised so as to project upwardly into the path of bolt 14 to assure engagement thereby during displacement from the recoil position.

Buffer-retainer 40 is actuated rearwardly, against the bias of spring 38, by the contact of a radial flange 56 on bolt 14 with the front side of plate 44 during the recoil strokes of bolt 14. Flange 56 is disposed adjacent the front end of bolt 14 so that tines 50 extend forwardly therebcyond when the flange and plate '44 are in contact. The contact of flange 56 with plate 44 during recoil travel of bolt 14, which displaces bufler-retainer 4t) rearwardly against the bias of spring 38, releases cartridge 22 engaged with the underside of tines 50. When released, such cartridge 22 is moved under the bias of spring 26 into pickup position in neck 24. Moreover,

3 through the engagement of buffer-retainer 40 by bolt 14, the energy therein is partially absorbed by spring 38, before being stopped in recoil position by the contact of plate 44 with wall 34, to provide a buffer for the bolt. The stored energy in spring 38 energizes bolt 14 for the succeeding counterrecoil stroke thereof.

Thus, when bolt 14 is in battery, the rear end of the leading cartridge 22 in magazine 20 is in engagement with the undersides of tines 50 so as to project radially upward therebetween but so as to be clear of flange 56, as shown in FIG. 1, when the bolt travels in recoil responsive to discharge forces. \Vhen bolt 14- is adjacent recoil position during the recoil stroke thereof, flange 56 contacts plate 44 to provide a buffer for the bolt and retract tines 50 within chamber section 32 for release of the engaged cartridge 22.

The released cartridge 22 is immediately biased upwardly into pickup position in neck 24 and the contact of plate 44 with wall 34 stops bolt 14 in the recoil position thereof. Spring 26 must have sufficient resiliency and the reciprocation of bulfer-retainer 40 with bolt 14- must be suflicient to assure that the released cartridge 22 will reach pickup position in neck 24 by the time that the front end of tines 50 are positioned, during counterrecoil of the bolt, for engagement with the underside of such cartridge. The ramps 52 on the front ends of tines 50 assure extension thereof beneath the leading cartridge 22. Therefore, the leading cartridge 22 is positively positioned by tines 50 so that, when stop 46 contacts the front end of slot 48 to stop the forward displacement of buffer-retainer 4t and bolt 14 continues in counterrecoil relative thereto, the base of such cartridge is isolated by tines t? from the influence of spring 26 and supported for positive contact by the front end of the bolt. When the leading cartridge 22 in magazine 20 is transferred therefrom by bolt 14, the succeeding cartridge in the magazine is pressed upwardly by spring 26 into engagement with the undersides of tines 50.

From the foregoing it is clearly apparent that there is provided herein a device which serves the dual purpose of retaining a cartridge in a magazine in position for positive contact by a reciprocating bolt and of buflflng the recoil strokes thereof, which buffer-retainer device is simple and rugged in construction and positive in its functions.

Although a particular embodiment of the invention has been described in detail herein, it is evident that many variations may be devised within the spirit and scope thereof and the following claims are intended to include such variations.

I claim:

1. In a firearm, the combination including a receiver, a bolt disposed in the receiver for longitudinal reciprocation to and from a recoil position, a magazine arranged for moving cartridges successively from a stored supply therein to a neck of said magazine and in position for pickup by said bolt during displacement thereof from the recoil position, and a device disposed in the receiver so as to be engageable with the pickup position cartridges for retention thereof in position for pickup by said bolt and so as to resiliently stop said bolt in the recoil position and energize said bolt for flight therefrom.

2. In a firearm, the combination including a receiver, a bolt disposed in the receiver so as to be energized for longitudinal reciprocation to and from a recoil position, a magazine arranged for moving cartridges therein successively and in contact relationship to a neck of said magazine in position for pickup by said bolt during displacement thereof from the recoil position, a bulfer-retainer device mounted for longitudinal reciprocation in the receiver adjacent said magazine, said buffer device including retainer means engageable with the pickup position cartridges for retention thereof in position for pickup by said bolt during displacement from the recoil position and spring means disposed for biasing said retainer means into engagement with the pickup position cartridges, and a flange disposed on said bolt for engagement with said buffer-retainer device during displacement of said bolt to the recoil position for actuating said retainer means so as to be displaceable into engagement with the pickup position cartridges and for transferring recoil energy from said bolt to said spring means to resiliently stop said bolt at the recoil position and energize said bolt for flight therefrom.

3. The combination as defined in claim 2 wherein said retainer means includes a pair of tines laterally disposed so as to be engageable with the pickup position cartridges on opposite sides of an area of contact of the pickup position cartridge with a succeeding cartridge in said magazine and so as to permit limited radial displacement of the succeeding cartridge therebetween when the pickup position cartridge is removed from said magazine by said bolt.

4. The combination as defined in claim 2 wherein the receiver is provided with a vertical well for receiving said magazine, a chamber section extending rearwardly from the top of said well to a vertically disposed wall and a bore extending longitudinally rearward therefrom; wherein said buffer-retainer device includes a shaft slidingly disposed in said bore, an integral plate laterally disposed on the front end of said shaft so as to be slidingly received by said chamber section and be contactable with said wall to stop rearward displacement of said buifer-retainer device and means for stopping the forward displacement thereof to limit the longitudinal reciprocation of said buffer-retainer device; wherein said retaining means includes a pair of tines extending integrally forward from said plate so that when the forward displacement of said buffer-retainer is stopped by said stopping means said tines extend into said magazine for engagement with the pickup position cartridge to support the cartridge for contact by said bolt during displacement from the recoil position and so that when said plate is in contact with said wall said tines are retracted from said magazine into said chamber section; wherein said spring means is disposed in said bore rearwardly of said shaft for biasing said buffer-retainer device forwardly; and wherein said flange is integrally disposed on said bolt adjacent the front end thereof so that when said flange and said plate are in contact said tines extend forwardly beyond said bolt to engage the pickup position cartridge before contact thereof by said bolt during flight thereof from the recoil position.