Weapon cartridge

Abstract

A cartridge for a small arms weapon, comprising a cover for housing a projectile; a metal cap at a rear end of the cover; a propellant charge located inside the cover at the rear thereof; and a gas seal element located inside the cover adjacent to the propellant charge and having an annular sealing formation projecting rearwardly towards the propellant charge and being outwardly deformable on detonation of the propellant charge for sealing against an internal surface of the cover. The metal cap has a rim extending longitudinally over a portion of the external surface of the cover for supporting the cover where the sealing formation first seals against its internal surface.

1 . A cartridge for a small arms weapon, comprising:
 a cover for housing a projectile;   a metal cap at a rear end of the cover;   a propellant charge located inside the cover at the rear thereof; and   a gas seal element located inside the cover adjacent to the propellant charge and having an annular sealing formation projecting rearwardly towards the propellant charge and being outwardly deformable on detonation of the propellent charge for sealing against an internal surface of the cover;   wherein the metal cap has a rim extending longitudinally over a portion of the external surface of the cover for supporting the cover where the sealing formation first seals against its internal surface.   
     
     
         2 . A cartridge according to  claim 1 , wherein the sealing formation is inclined radially outward. 
     
     
         3 . A cartridge according to  claim 1 , wherein the gas seal element has a disc shaped body. 
     
     
         4 . A cartridge according to  claim 1 , wherein gas seal element further comprises a notch at a base of the sealing formation for directing its deformation outwardly. 
     
     
         5 . A cartridge according to  claim 1 , wherein the gas seal element has a disc shaped body and further comprises a notch at a base of the sealing formation for directing its deformation outwardly, wherein the notch is formed on a circumferential surface of the disc shaped body. 
     
     
         6 . A cartridge according to  claim 1 , wherein the gas seal element further comprises a formation for receiving the rear of a projectile. 
     
     
         7 . A cartridge according to  claim 1 , further comprising a projectile at least partially received inside the cover. 
     
     
         8 . A cartridge according to  claim 1 , wherein the cover is formed of a plastic material. 
     
     
         9 . A cartridge according to  claim 1 , wherein the metal cap comprises brass. 
     
     
         10 . A cartridge according to  claim 1 , wherein the rim of the metal cap extends beyond the longitudinal position where the sealing formation projects from the gas seal element's body. 
     
     
         11 . A cartridge according to  claim 1 , wherein the sealing formation defines a central depression in the rear surface of the gas seal element. 
     
     
         12 . A cartridge according to  claim 11 , wherein the propellant charge is at least partially received into the central depression. 
     
     
         13 . A cartridge according to  claim 11 , wherein the central depression has a cone shaped profile for directing expanding gases radially outward toward the inward facing surface of the sealing formation. 
     
     
         14 . A cartridge according to  claim 1 , wherein the rim of the metal cap extends to a longitudinal position between the front of the gas seal element and the position where the sealing formation projects from the gas seal element's body. 
     
     
         15 . A cartridge comprising:
 a plastic casing having a metal cap formed over one end for forming a supported region inside the casing;   a propellant charge provided inside the casing, adjacent to the metal cap; and   a gas seal located inside the casing and having a rearward surface comprising a circumferential wall projecting toward the propellant charge;   wherein the circumferential wall is configured to deform outwardly on detonation of the propellant charge for contact with the supported region of the casing so that the supported region of the casing is compressed between a distal edge of the circumferential wall and a rim of the metal cap.