Patent Publication Number: US-11029115-B2

Title: Firing pin retainer and firearm operating system including same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of and priority to U.S. Provisional Application No. 62/760,246, filed on Nov. 13, 2018, the content of which is herein incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to firearms. 
     BACKGROUND 
     Certain firearms include an upper receiver (e.g., a continuous aluminum extrusion, folded sheet metal, tube, casting, etc.) that houses the recoiling parts, barrel, charging handle, and possibly lugs, which allow it to fasten to a lower receiver or trigger group. Some firearms, such as those with piston-type gas operated autoloading systems, include an operating rod that attaches to a bolt carrier by a lug received in a pocket of the bolt carrier. 
     Gas operated autoloading systems are known for cycling the action in auto-loading semi-automatic and automatic rifles. Gas operated autoloading systems use a portion of the high energy combustion gases from discharging the firearm to cycle the action for extracting a spent cartridge case and chambering a new round. After the firearm has been fired, the exhaust gases act on and move a piston and an operating rod that is operatively connected to the bolt carrier. The movement of the operating rod moves the bolt carrier rearward (in the direction opposite to the fired bullet) and to a retracted position. Once the piston has traveled a certain distance, a spring acting on the assembly will then move the operating rod and accompanying bolt carrier forward, picking up a new cartridge, and moving that cartridge into the battery position. 
     SUMMARY 
     Various embodiments relate to a firearm operating system. An example firearm operating system includes a firing pin having a first end and a second end. An operating rod assembly includes an operating rod, a lug positioned at a first end of the operating rod, and a firing pin retainer extending from the lug. A bolt carrier includes a bolt carrier pocket structured to receive the firing pin retainer of the operating rod assembly, and a bolt carrier cam pin opening. A bolt is structured to be received in the bolt carrier. The bolt includes a bolt cam pin opening. A cam pin includes a firing pin opening. The cam pin is structured to be positioned through the bolt carrier cam pin opening and into the bolt cam pin opening. The first end of the firing pin extends through the firing pin opening of the cam pin to retain the cam pin. The firing pin retainer of the operating rod assembly engages the second end of the firing pin so as to retain the firing pin. A chambered round is fired in response to a hammer striking the firing pin. 
     Various other embodiments relate to a firearm operating system. An example firearm operating system includes a firing pin having a first end and a second end. An operating rod assembly includes an operating rod, and a lug positioned at a first end of the operating rod. A bolt includes a bolt pocket structured to receive the lug of the operating rod assembly. The lug engages a firing pin retainer located at the second end of the firing pin so as to retain the firing pin. A chambered round is fired in response to the operating rod driving the firing pin forward. 
     Various additional embodiments relate to a firearm operating system. An example firearm operating system includes a firing pin comprising a first end and a second end. An operating rod assembly includes an operating rod and a tail extending below a first end. A bolt carrier defines a recess and a slot, the slot being positioned transverse to the recess, the recess configured to receive the tail. An elongate firing pin retainer is sized to be slidably received by the slot, and the tail contacts the elongate firing pin retainer when the recess receives the tail. The elongate firing pin retainer engages the second end of the firing pin so as to retain the firing pin. 
     This summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the devices and/or processes described herein, as defined solely by the claims, will become apparent in the detailed description set forth herein, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of a firearm gas operated autoloading system  100 , according to an embodiment. 
         FIG. 2  illustrates various other views of the firearm gas operated autoloading system  100  of  FIG. 1 . 
         FIG. 3  illustrates a perspective view of another firearm gas operated autoloading system  200 , according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Before turning to the figures, which illustrate the exemplary embodiments in detail, it should be understood that the present disclosure is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology used herein is for the purpose of description only and should not be regarded as limiting. 
       FIG. 1  is an exploded view of a firearm gas operated autoloading system  100 , according to an embodiment. The gas operated autoloading system  100  comprises a firing pin  102 , an operating rod assembly  104 , a bolt carrier  106 , a bolt  108 , and a cam pin  110 . 
     The firing pin  102  comprises a first end  112  and a second end  114 . 
     The operating rod assembly  104  comprises an operating rod  116 , a lug  118 , and a firing pin retainer  120 . The lug  118  is positioned at a first end  122  of the operating rod  116 . The firing pin retainer  120  extends from the lug  118 . In some implementations, the lug  118  itself operates as the firing pin retainer  120 . 
     The bolt carrier  106  comprises a bolt carrier pocket  124  and a bolt carrier cam pin opening  126 . The bolt carrier pocket  124  is structured to receive the firing pin retainer  120  of the operating rod assembly  104 . The firing pin retainer  120  extends through the bolt carrier pocket  124 . 
     The bolt  108  comprises a bolt cam pin opening  128 . The bolt  108  is structured to be received in the bolt carrier  106 . 
     The cam pin  110  comprises a firing pin opening  130 . The cam pin  110  is structured to be positioned through the bolt carrier cam pin opening  126  and into the bolt cam pin opening  128 . 
     The first end  112  of the firing pin  102  extends through the firing pin opening  130  of the cam pin  110  to retain the cam pin  110 . The firing pin retainer  120  of the operating rod assembly  104  engages the second end  114  of the firing pin  102  so as to retain the firing pin  102 . 
     Other firearms use pins, levers or other mechanisms that require manipulation to remove the firing pin  102  from the recoiling parts of the firearm gas operated autoloading system  100 . According to various embodiments, and as illustrated in  FIG. 1 , the cam pin  110 , which is inserted into the bolt cam pin opening  128  of the bolt  108 , keeps the bolt  108  in place. The firing pin  102 , which passes through the firing pin opening  130  of the cam pin  110 , keeps the cam pin  110  in place. Thus, a firearm implementing the firearm gas operated autoloading system  100  enables separation of the upper and lower receiver and removal of the recoiling parts out of the back of the upper receiver. The recoiling parts all come apart in seconds without any tools or any further manipulation of pins, levers, etc. The same benefit is provided when the firearm gas operated autoloading system  100  is used with guns that have a receiver and a trigger group (e.g., M-60, M-240, M-249, etc.) rather than separate upper and lower receivers. 
     Various embodiments described herein are directed to firearms in which a chambered round is fired in response to a hammer (not shown) striking the firing pin  102 . As noted above, the firearm gas operated autoloading system  100  is structured such that the firing pin retainer  120  of the operating rod assembly  104  operates to retain the firing pin  102 , thereby eliminating the need for pins, levers, or other mechanisms to retain the firing pin  102 , as with existing systems. The firing pin retainer  120  is structured so as to not interfere with the operation of the hammer to strike the firing pin to fire a round. 
     Various other embodiments described herein are directed to other types of firearms (e.g., M-60, M-240, M-249, etc.) in which a chambered round is fired in response to the operating rod  116  driving the firing pin  102  forward. These types of firearms typically include pins or caps to retain the firing pin. In contrast, various embodiments structured for use with firearms in which the operating rod  116  drives the firing pin  102  forward to fire the firearm do not include such pins or caps, but instead utilize the firing pin retainer  120  of the operating rod assembly  104  to retain the firing pin  102 . 
     In various other embodiments described herein, the operating rod  116  is not inserted into the bolt carrier  106 , but instead interfaces with the bolt carrier  106  in a different way. For example, the bolt carrier  106  may be slidably received by the operating rod  116  (e.g., the bolt carrier may include an operating rod cavity sized to receive the operating rod), the bolt carrier may include other structures to contact and interface with the operating rod  116 , etc. In such embodiments, the firing pin retainer  120  is movable and therefore must be actuated to function properly. Such actuation can occur when the operating rod  116  and the bolt carrier  106  interface with each other. In embodiments where the firing pin retainer  120  is movable, the firing pin retainer  120  may be held in the bolt carrier  106  or the operating rod  116  by a variety of different holding mechanisms (e.g., pins, screws, detents, snap-fit, etc.). During actuation, the firing pin retainer  120  can translate relative to the operating rod  116  (e.g., the firing pin retainer  120  can move forward or rearward along a longitudinal axis of the operating rod). As another example, the firing pin retainer  120  can rotate relative to the operating rod  116 . 
       FIG. 2  illustrates various other views of the firearm gas operated autoloading system  100  of  FIG. 1 . 
       FIG. 3  illustrates a perspective view of another firearm gas operated autoloading system  200 , according to an embodiment. An operating rod  204  includes a lug that is configured to interface with a recess  216  in a bolt carrier  206 . The bolt carrier  206  defines a slot  208  positioned transversely to the recess  216 , and the slot  208  extends below the recess  216 . An elongate firing pin retainer  210  is sized to be received by the slot  208  and contact the second end  114  of the firing pin  102  so as to retain the firing pin  102  when the firearm gas operated autoloading system  200  is assembled. The bolt  108  and firing pin  102  are assembled into the bolt carrier  206  in substantially the same manner as described with respect to  FIGS. 1-2 . The firing pin retainer  210  is slidably inserted into the slot  208 , and can be freely moved up and down until the operating rod  204  is assembled to the bolt carrier  206 . After assembling the operating rod  204  to the bolt carrier  206 , the firing pin retainer  210  is secured in place. Assembled as described, the firing pin retainer  210  (and hence the firing pin  102 ) can be easily removed from the firearm gas operated autoloading system  200  after removing the operating rod  204  from the bolt carrier  206 . 
     It should be noted that the term “exemplary” and variations thereof, as used herein to describe various embodiments, are intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such terms are not intended to connote that such embodiments are necessarily extraordinary or superlative examples). 
     It is important to note that the construction and arrangement of the system as shown in the various exemplary embodiments is illustrative only. Additionally, any element disclosed in one embodiment may be incorporated or utilized with any other embodiment disclosed herein. Although only one example of an element from one embodiment that can be incorporated or utilized in another embodiment has been described above, it should be appreciated that other elements of the various embodiments may be incorporated or utilized with any of the other embodiments disclosed herein.