Compact firearm

Abstract

Firearms have a lower frame including a trigger and a grip, an upper frame including a barrel and a bolt, and a magazine receptacle configured to receive a magazine and positioned between the upper and lower frames. The lower frame and upper frame may each have forward portions pivotally connected to each other to form a pivotal connection. The pivotal connection may be operable to pivot on a horizontal axis transverse to the firearm. The upper and lower frames may be movable between an open position in which the upper and lower frame are angularly separated from each other and the magazine receptacle is accessible for removal and replacement of a magazine, and a closed position in which the magazine is closely received between the upper and lower frames. The magazine receptacle may be laterally open on both sides of the firearm.

I claim: 
     
         1 . A firearm comprising:
 a lower frame including a trigger and a grip;   an upper frame including a barrel and a bolt and configured to separate from the lower frame; and   a magazine receptacle configured to receive a magazine and positioned between the upper and lower frames.   
     
     
         2 . The firearm of  claim 1  wherein the lower frame and upper frame each have forward portions pivotally connected to each other to form a pivotal connection. 
     
     
         3 . The firearm of  claim 2  wherein the pivotal connection is operable to pivot on a horizontal axis transverse to the firearm. 
     
     
         4 . The firearm of  claim 1  wherein the upper and lower frames are movable between an open position in which the upper and lower frame are angularly separated from each other and the magazine receptacle is accessible for removal and replacement of a magazine, and a closed position in which the magazine is closely received between the upper and lower frames. 
     
     
         5 . The firearm of  claim 4  wherein the magazine receptacle is laterally open on both sides of the firearm, such that a major portion of lateral edges of the magazine is exposed when the frames are in the closed position. 
     
     
         6 . The firearm of  claim 4  wherein the magazine is an elongated body having major opposed upper and lower faces, and elongated side edges. 
     
     
         7 . The firearm of  claim 6  wherein the side edges are exposed when the frames are in the closed position. 
     
     
         8 . The firearm of  claim 6  wherein the magazine includes an ammunition exit facility at the upper surface and wherein the upper frame bolt is operable to strip a cartridge from the ammunition exit facility. 
     
     
         9 . The firearm of  claim 8  wherein the ammunition exit facility is at a rear end of the magazine. 
     
     
         10 . The firearm of  claim 1  wherein the barrel has a muzzle end proximate a forward end of the magazine receptacle. 
     
     
         11 . The firearm of  claim 1  wherein the upper and lower frames are pivotally connected on a hinge axis at a level below the magazine receptacle. 
     
     
         12 . The firearm of  claim 1  wherein the magazine receptacle has a rear end proximate the grip. 
     
     
         13 . The firearm of  claim 1  wherein the upper frame includes a forward barrier defining a forward portion of the magazine receptacle. 
     
     
         14 . The firearm of  claim 1  wherein the upper frame includes a reciprocating bolt assembly operable to move between a forward battery position and a rear retracted position, the bolt assembly having a forward portion forward of a breech end of the barrel when in the forward battery position. 
     
     
         15 . The firearm of  claim 14  wherein the forward portion of the bolt assembly is forward of a breech end of the barrel when the bolt assembly is in the retracted position. 
     
     
         16 . The firearm of  claim 14  wherein the bolt assembly has a center of mass forward of a breech end of the barrel when the bolt assembly is in the forward battery position. 
     
     
         17 . The firearm of  claim 14  wherein the bolt assembly has a forward portion proximate a muzzle end of the barrel when in the forward battery position. 
     
     
         18 . The firearm of  claim 14  wherein the bolt assembly has a rear portion rearward of the barrel and having a breech face, an elongated connector element having a rear end connected to the rear portion of the bolt assembly and an opposed forward end, and a forward weight connected to the forward end of the connector element. 
     
     
         19 . The firearm of  claim 18  wherein the forward weight defines a channel receiving the barrel and having opposed side portions on opposite lateral sides of the barrel.