Cartridge and cartridge case

Abstract

Cartridges and cartridge cases adapted to be chambered in weapon systems are provided. In one example, a cartridge case includes a front shell having a case base end portion, a case body portion extending forward from the case base end portion towards a case mouth portion that is configured for holding a projectile. The case base end portion has a first interlocking feature. A reinforcing cap is disposed adjacent to the case base end portion on a side opposite the internal volume. The reinforcing cap has an annular extraction groove, a primer pocket, a flash hole for providing fluid communication between the primer pocket and the internal volume, and a second interlocking feature that engages the first interlocking feature to couple the reinforcing cap to the case base end portion.

What is claimed is: 
     
         1 . A cartridge case adapted to be chambered in a weapon system, the cartridge case comprising:
 a generally cylindrical front shell having a shell wall that surrounds an internal volume for containing a propellant, wherein the shell wall defines a case base end portion, a case body portion extending forward from the case base end portion towards a case mouth portion that is configured for holding a projectile, and wherein the case base end portion has a first interlocking feature; and   a reinforcing cap disposed adjacent to the case base end portion on a side opposite the internal volume, wherein the reinforcing cap has an annular extraction groove, a primer pocket, a flash hole for providing fluid communication between the primer pocket and the internal volume, and a second interlocking feature that extends inwardly towards the first interlocking feature to define a rib edge that is rounded, radiused, relatively sharp or pointed and that engages the first interlocking feature to couple the reinforcing cap to the case base end portion of the generally cylindrical front shell.   
     
     
         2 . The cartridge case of  claim 1 , wherein the generally cylindrical front shell comprises a first metallic material and the reinforcing cap comprises a second relatively lightweight metallic material. 
     
     
         3 . The cartridge case of  claim 2 , wherein the second relatively lightweight metallic material is different than the first metallic material. 
     
     
         4 . The cartridge case of  claim 2 , wherein the first metallic material is selected from carbon steel, stainless steel, brass, aluminum, aluminum alloys, nickel, and nickel alloys. 
     
     
         5 . The cartridge case of  claim 4 , wherein the first metallic material is stainless steel. 
     
     
         6 . The cartridge case of  claim 2 , wherein the second relatively lightweight metallic material is selected from aluminum and alloys thereof, titanium and alloys thereof, magnesium and alloys thereof. 
     
     
         7 . The cartridge case of  claim 6 , wherein the second relatively lightweight metallic material is an aluminum alloy. 
     
     
         8 . The cartridge case of  claim 1 , wherein the shell wall has a substantially constant wall thickness. 
     
     
         9 . The cartridge case of  claim 1 , wherein the case base end portion has a bulge section that forms at least part of the first interlocking feature. 
     
     
         10 . The cartridge case of  claim 9 , wherein the bulge section comprises an annular bulge section. 
     
     
         11 . The cartridge case of  claim 9 , wherein the reinforcing cap comprises a locking rib that includes the rib edge and that forms at least part of the second interlocking feature. 
     
     
         12 . The cartridge case of  claim 11 , wherein the locking rib comprises an annular locking rib. 
     
     
         13 . The cartridge case of  claim 11 , wherein the case base end portion has a recessed feature that forms at least part of the first interlocking feature. 
     
     
         14 . The cartridge case of  claim 13 , wherein the recessed feature is an annular recessed feature. 
     
     
         15 . The cartridge case of  claim 13 , wherein the first interlocking feature has a plurality of spaced apart recessed features and the second interlocking feature has a plurality of spaced apart locking ribs that correspondingly engage the plurality of the spaced apart recessed features. 
     
     
         16 . The cartridge case of  claim 1 , wherein the first and second interlocking features are directly engaged with each other to ensure an air-tight seal between the reinforcing cap and the front shell without the presence of any liquid and/or solid seal(s). 
     
     
         17 . A cartridge adapted to be chambered in a weapon system, the cartridge comprising:
 a cartridge case comprising:
 a generally cylindrical front shell having a shell wall that surrounds an internal volume, wherein the shell wall defines a case base end portion, a case body portion extending forward from the case base end portion towards a case mouth portion, wherein the case base end portion has a first interlocking feature; and 
 a reinforcing cap disposed adjacent to the case base end portion on a side opposite the internal volume, wherein the reinforcing cap has an annular extraction groove, a primer pocket, a flash hole for providing fluid communication between the primer pocket and the internal volume, and a second interlocking feature that extends inwardly towards the first interlocking feature to define a rib edge that is rounded, radiused, relatively sharp or pointed and that engages the first interlocking feature to couple the reinforcing cap to the case base end portion of the generally cylindrical front shell; 
 a projectile disposed in the case mouth portion; 
 a propellant disposed in the internal volume and ignitable to propel the projectile from the case mouth in a forward direction; and 
 a primer disposed in the primer pocket and ignitable for igniting the propellant. 
   
     
     
         18 . The cartridge case of  claim 17 , wherein the reinforcing cap has a locking rib that includes the rib edge and that forms at least part of the second interlocking feature. 
     
     
         19 . The cartridge case of  claim 18 , the case base end portion has a recessed feature that forms at least part of the first interlocking feature. 
     
     
         20 . The cartridge case of  claim 19 , wherein the first interlocking feature has a plurality of axially spaced apart recessed features and the second interlocking feature has a plurality of axially spaced apart locking ribs that correspondingly engage the plurality of the axially spaced apart recessed features.