Firearm

Abstract

An improvement to a firearm of the character having an upper receiver, an operating rod operably associated with the upper receiver for movement between a first position and a second position, and a lower receiver connected to the upper receiver. The improvement concerns a novel bolt and barrel lock and release mechanism carried by the upper receiver and a novel trigger mechanism carried by the lower receiver.

1 . In combination, a firearm having an upper receiver, an operating rod operably associated with said upper receiver for movement between a first position and a second position, a lower receiver connected to said upper receiver, a trigger mechanism carried by said lower receiver and a magazine connected to said lower receiver for carrying a plurality of ammunition cartridges, the improvement comprising:
 (a) a barrel connected to said upper receiver, said barrel having a rear portion having a guide slot and a curved bearing surface and an intermediate portion having a gas transfer passageway formed therein;   (b) a generally semi-circular receiver bearing formed in said upper receiver;   (c) a bolt slidably received within said upper receiver for movement between a first forward position and a second rearward position, said bolt having a longitudinally extending guide slot;   (d) a firing pin carried by said bolt for movement between a first position and a second position;   (e) a striker connected to said bolt for movement between a first position and a second position in engagement with said firing pin;   (f) a locking member removably connected to said upper receiver for movement relative thereto between a first bolt engaging position and a second bolt disengage position, said locking member having a rearward portion, a central portion having a locking shoulder and a curved forward portion received within said generally semi-circular bore of said upper receiver and within said curved bearing surface of said barrel;   (g) locking member biasing means carried by said upper receiver for urging said locking member into said first bolt engaging position;   (h) a disengage member slidably received within said longitudinally extending guide slot of said bolt and within said guide slot of said barrel for movement by said operating rod between a first position and a second position, said disengage member having a wall for engagement with said locking member to move said locking member into said bolt disengage position upon movement of said disengage member to said second position; and   (i) a trigger mechanism carried by said lower receiver and operably associated with said striker, said trigger mechanism including:
 i. a trigger housing; 
 ii. a trigger assembly pivotally connected to said trigger housing for movement from a first position to a second position said trigger assembly including a finger engaging trigger portion having sides; and 
 iii. a first safety mechanism, including a swinging anchor pivotally connected to said trigger housing for movement between a first position in alignment with said finger engaging trigger portion and a second position proximate one side of said finger engaging trigger portion. 
   
     
     
         2 . The firearm as defined in  claim 1  in which said improvement further comprises a second safety mechanism rotatably carried by said lower receiver, said second safety mechanism being operably associated with said trigger mechanism and comprising:
 (a) a pair of spaced apart plates; 
 (b) a connector rod interconnecting said pair of spaced apart plates; and 
 (c) a trigger blocking member connected to said connector rod and extending outwardly therefrom. 
 
     
     
         3 . The firearm as defined in  claim 1  in which said improvement further comprises a striker stop pin carried by said bolt and operably associated with said locking member for movement thereby between a first position blocking movement of said firing pin and a second position permitting movement of said firing pin. 
     
     
         4 . The firearm as defined in  claim 1  in which said improvement further comprises a receiver extension connected to and extending from said upper receiver, said receiver extension comprising a shoulder engaging stock provided with an elongated cavity and further including a recoil spring mounted within said elongated cavity. 
     
     
         5 . The firearm as defined in  claim 1  in which said trigger mechanism further includes a de-cocking member for de-cocking said firearm, said de-cocking member being operably associated with said striker and being pivotally connected to said upper receiver for movement between a first position and a second position, said de-cocking member comprising a body portion, a pivot shaft about which said body portion pivots and a torsion spring surrounding said pivot shaft for continuously resisting rotation of said de-cocking member. 
     
     
         6 . In combination, a firearm having an upper receiver, a barrel connected to said upper receiver, an operating rod carried by and operably associated with said barrel for movement between a first position and a second position, a lower receiver connected to said upper receiver and a magazine connected to said lower receiver for carrying a plurality of ammunition cartridges, the improvement comprising:
 (a) a generally semi-circular receiver bearing formed in said upper receiver;   (b) a bolt slidably received within said upper receiver for movement between a first forward position and a second rearward position, said bolt having a longitudinally extending guide slot;   (c) a firing pin carried by said bolt for movement between a first position and a second position;   (d) a striker connected to said bolt for movement between a first position and a second position in engagement with said firing pin;   (e) a locking member removably connected to said upper receiver for movement relative thereto between a first bolt engaging position and a second bolt disengage position, said locking member having a rearward portion, a central portion having a locking shoulder and a curved forward portion received within said generally semi-circular bore of said upper receiver;   (f) locking member biasing means carried by said upper receiver for urging said locking member into said first bolt engaging position;   (g) a disengage member slidably received within said longitudinally extending guide slot of said bolt for movement by said operating rod between a first position and a second position, said disengage member having a wall for engagement with said locking member to move said locking member into said bolt disengage position upon movement of said disengage member to said second position;   (h) a sear operably associated with said striker, said sear being pivotally connected to said upper receiver for movement between first and second positions;   (i) a trigger mechanism connected to said lower receiver, said trigger mechanism comprising:
 i. a trigger housing; 
 ii. a lift bar pivotally connected to said trigger housing, said lift bar having a first end, a second end and an intermediate portion; 
 iii. a trigger pivotally connected to said trigger housing and operably associated with said lift bar for lifting said first end of said lift bar upon pivotal movement of said trigger, said trigger including a finger engaging portion having sides; and 
 iv. a lifter member pivotally connected to said lift bar for movement between a first position and a second position to engage said sear to move said sear towards said second position of said sear; and 
   (j) a first safety mechanism, including a swinging anchor pivotally connected to said trigger housing for movement between a first position in alignment with said finger engaging trigger portion and a second position proximate one side of said finger engaging trigger portion.   
     
     
         7 . The combination as defined in  claim 6  in which said sear includes a shoulder for engaging said striker when said striker is in said first position. 
     
     
         8 . The combination as defined in  claim 6  in which said trigger includes a transversely extending pivot pin and in which said intermediate portion of said locking member is provided with a groove for receiving said transversely extending pivot pin. 
     
     
         9 . The firearm as defined in  claim 6  in which said improvement further comprises a second safety mechanism rotatably carried by said lower receiver, said second safety mechanism being operably associated with said trigger and comprising:
 (a) a pair of spaced apart plates; 
 (b) a connector rod interconnecting said pair of spaced apart plates; and 
 (c) a trigger blocking member connected to said connector rod and extending outwardly therefrom. 
 
     
     
         10 . The firearm as defined in  claim 6  in which said improvement further comprises a striker stop pin carried by said bolt and operably associated with said locking member for movement thereby between a first position blocking movement of said firing pin and a second position permitting movement of said firing pin. 
     
     
         11 . In combination, a firearm having an upper receiver, a barrel connected to said upper receiver, an operating rod carried by and operably associated with said barrel for movement between a first position and a second position, a lower receiver connected to said upper receiver and a magazine connected to said lower receiver for carrying a plurality of ammunition cartridges, the improvement comprising:
 (a) a generally semi-circular receiver bearing formed in said upper receiver;   (b) a bolt slidably received within said upper receiver for movement between a first forward position and a second rearward position, said bolt having a longitudinally extending guide slot;   (c) a firing pin carried by said bolt for movement between a first position and a second position;   (d) a striker connected to said bolt for movement between a first position and a second position in engagement with said firing pin;   (e) a locking member removably connected to said upper receiver for movement relative thereto between a first bolt engaging position and a second bolt disengage position, said locking member having a rearward portion, a central portion having a locking shoulder and a curved forward portion received within said generally semi-circular bore of said upper receiver;   (f) locking member biasing means carried by said upper receiver for urging said locking member into said first bolt engaging position;   (g) a disengage member slidably received within said longitudinally extending guide slot of said bolt for movement by said operating rod between a first position and a second position, said disengage member having a wall for engagement with said locking member to move said locking member into said bolt disengage position upon movement of said disengage member to said second position;   (h) a sear operably associated with said striker, said sear being pivotally connected to said upper receiver for movement between first and second positions; and   (i) a trigger mechanism connected to said lower receiver, said trigger mechanism comprising:
 i. a trigger housing; 
 ii. a lift bar pivotally connected to said trigger housing, said lift bar having a first end, a second end and an intermediate portion; 
 iii. a trigger pivotally connected to said trigger housing and operably associated with said lift bar for lifting said first end of said lift bar upon pivotal movement of said trigger, said trigger including a finger engaging portion having sides; 
 iv. a lifter member pivotally connected to said lift bar for movement between a first position and a second position to engage said sear to move said sear towards said second position of said sear; 
 v. a first safety mechanism, including a swinging anchor pivotally connected to said trigger housing for movement between a first position in alignment with said finger engaging trigger portion and a second position proximate one side of said finger engaging trigger portion; and 
 vi. a second safety mechanism rotatably carried by said lower receiver, said second safety mechanism being operably associated with said trigger and comprising:
 a. a pair of spaced apart plates; 
 b. a connector rod interconnecting said pair of spaced apart plates; and 
 c. a trigger blocking member connected to said connector rod and extending outwardly therefrom. 
 
   
     
     
         12 . The firearm as defined in  claim 11  in which said improvement further comprises a striker stop pin carried by said bolt and operably associated with said locking member for movement thereby between a first position blocking movement of said firing pin and a second position permitting movement of said firing pin.