Stock assembly and recoil system for a firearm

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 61/750,898, filed 10 Jan. 2013.

[0002] This invention relates to firearms.

[0003] More particularly, the present invention relates to stocks for firearms.

[0004] In the field of firearms, and in particular shoulder fired firearms, it is desirable to have a shortened profile for ease in use and increase portability. It is also desirable that the shortening of the firearm does not adversely impact the performance of the firearm. While firearms are often shortened by reducing barrel length, the length of the barrel has a great impact on the range and accuracy of the firearm. It would therefore be advantageous to reduce the length of the firearm without necessarily reducing the length of the barrel, limiting the reduction of the barrel or reducing the length of the barrel as far as possible and still further reducing the length of the firearm. Reducing the length of the firearm separate from the barrel length requires that reducing the length of the firearm behind the receiver be contemplated. In some types of shoulder fired firearms a stock extends rearwardly from the receiver. To enhance accuracy and usability, as well as being a part of the operating system, these firearms employ a buffering system carried rearward of the receiver and within the stock. However, buffering systems carried rearward of the receivers of the firearm typically result in an inability to shorten that same firearm. Thus, to shorten the firearm, the buffer system must be removed, adversely affecting the operation of the firearm.

[0005] It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.

[0006] An object of the present invention is to provide a shortened stock assembly and recoil system for a firearm.

[0007] Briefly, to achieve the desired objects and advantages of the instant invention, provided is a stock and recoil system for a firearm including a lower receiver having a forward end and a rearward end, a bolt carrier, and a stock assembly. The bolt carrier is reciprocally movable along an axis within an upper receiver carried by the lower receiver and includes a tubular rearward end defining a cavity with a rearwardly directed opening. The stock assembly is coupled to the rearward end of the lower receiver and includes a receiver extension having a forward end coupled to the rearward end of the lower receiver aligned on the axis and a closed rearward end. An action spring is carried within the receiver extension and extends from the closed rearward end passed the forward end and is received by the tubular rearward end of the bolt carrier. The action spring is movable between a compressed configuration and an expanded configuration. A butt plate is adjustably coupled to the receiver extension and is movable between an extended position and a collapsed position.

[0008] Also provided is a bolt carrier which can include an inner carrier weight received within and coupled to the tubular rearward end of the bolt carrier. A kinetic weight is reciprocally movable rearwardly and forwardly on the tubular rearward end of the bolt carrier, and is retained on the bolt carrier by the inner carrier weight.

[0017] Turning now to the drawings in which like reference characters indicate corresponding elements throughout the several views, attention is first directed to FIGS. 1 and 2 which illustrate a portion of a firearm generally designated 10. Firearm 10 includes a lower receiver 12 having a forward end 14 and a rearward end 15, a bolt carrier system 16 reciprocally movable along an axis designated A within an upper receiver 17 (shown by broken lines) carried by and positioned above lower receiver 12, and a stock assembly 18 coupled to rearward end 15 of lower receiver 12. In the present invention, the preferred firearm used in conjunction with the stock and the recoil system is an AR15/M16 type firearm, although it will be understood that similar systems can be employed. The stock and recoil system of the present invention shortens the conventional carbine AR15 recoil system to allow a more compact firearm. Lower receiver 12 will not be described in detail, as it is well known to those of ordinary skill in the art, other than to detail a threaded receptacle 20 which normally receives a buffer tube used in conventional firearms of this type. In conventional firearms of this type, the length of the firearm can be reduced only to certain limits, such as the length of the buffer tube. In the present invention, the buffer tube is removed, and replaced with a receiver extension 22. The receiver extension is preferably substantially shorter than the buffer tube, such as 4 or more inches shorter. This allows the firearm to be that much shorter, as will be described presently.

[0018] Stock assembly 18 includes receiver extension 22 which is a generally tubular member having a threaded forward end 23 threadably received by threaded receptacle 20, a closed rearward end 24 and an encircling raised collar 25 extending radially outwardly from an outer surface thereof intermediate forward end 23 and rearward end 24. Raised collar 25 includes a plurality of detent grooves 28 extending longitudinally therealong and formed around a circumference thereof. Stock assembly 18 further includes a butt plate 30 coupled to receiver extension 22 by a stock knuckle 32. Stock knuckle 32 has a tubular portion 33 and a guide portion 35 extending from a lower surface thereof. Tubular portion 33 of stock knuckle 32 is received over forward end 23 of receiver extension 22 and captured between raised collar 25 and threaded receptacle 20. An adjustment mechanism 38 is carried by guide portion 35.

[0019] Butt plate 30 is adjustably coupled to guide portion 35 of stock knuckle 32 by a pair of stock rods 40 extending from butt plate 30 and slidably received by guide portion 35 on opposing sides of stock knuckle 32. With additional reference to FIGS. 3, 4 and 5, in the fully collapsed position, butt plate 30 slides over rearward end 24 of receiver extension 22, the rearward end of the receiver extension being received in a cavity 41 defined in butt plate 30, reducing overall length. In the fully collapsed position, stock rods 40 are positioned to either side of lower receiver 12. The firearm is fully functional in this configuration with stock rods 40 not affecting the firing of the firearm. Stock rods 40 each include predetermined stock length adjustment locking notches 42 to allow adjustment of the stock between a fully collapsed position and a fully extended position. Stock rods 40 each further include a groove 44 on an inwardly directed surface thereof, extending from proximate a forward end to a position spaced from a rearward end thereof. Grooves 44 receive a spring loaded detent inside guide portion 35 above adjustment mechanism 38 that limits the range of movement of stock rods 40 through knuckle 32 so that butt plate 30 will not be able to be completely removed without releasing the detents. Preferably, the stock rod detents and spring are held in place independently of adjustment mechanism 38.

[0020] Still referring to FIGS. 1-3, with additional reference to FIGS. 4 and 6, adjustment mechanism 38 includes a pivoting latch 50 having a detent end 52 and a biased end 54. Latch 50 pivots about a central pivot point 55 between a locked and an unlocked position. In the locked position, detent end 52 forces a detent member 58 upwardly to engage receiver extension 22. Biased end 54 is biased to retain latch 50 in the locked position by springs 59. Receiver extension 22 is self-locking by the insertion of detent member 58 into one of detent grooves 28. When latch 50 is moved to the unlocked position, receiver extension 22 can be threaded or unthreaded from threaded receptacle 20. When latch 50 is in the locked position, detent member 58 prevents rotation of receiver extension 22, locking it in place. In this manner, receiver extension 22 is securely coupled to receiver 12, but can be removed and installed easily by hand. It should be noted that latch 50 is in line with locking notches 42 on rods 40 so that the direction of the force will not allow the stock to adjust from impact.

[0021] Still referring to FIGS. 1 and 2, with additional reference to FIG. 7, bolt carrier system 16 includes a bolt carrier 60 having a tubular rearward end 61 defining a cavity with a rearwardly directed opening, an inner carrier weight 62 received within and coupled to tubular rearward end of bolt carrier 60, and a kinetic weight 64. Kinetic weight 64 moves reciprocally rearwardly and forwardly on tubular rearward end 61 of bolt carrier 60 to prevent bolt bounce. Inner carrier weight 62 includes a flange 63 which keeps kinetic weight 64 from coming off bolt carrier 60 when the firearm cycles. An action spring 70 is carried within receiver extension 22 and extends from rearward end 24 passed forward end 23 and is received through inner carrier weight 62 and into tubular rearward end 61 within bolt carrier system 16. Action spring 70 fits into inner carrier weight 62 and allows bolt carrier 60 to cycle, giving the spring the area needed to reach its solid compressed state without over stressing the spring. Action spring 70 is received over a spring guide 72 extending longitudinally through receiver extension from rearward end 24, for proper spring compression and alignment.

[0022] Various changes and modifications to the embodiments herein chosen for purposes of illustration will readily occur to those skilled in the art. To the extent that such modifications and variations do not depart from the spirit of the invention, they are intended to be included within the scope thereof, which is assessed only by a fair interpretation of the following claims.