Cartridges and modifications for m16/ar15 rifle

Abstract

Embodiments of the present invention relate generally to cartridges and modifications for an M16/AR15 rifle. In one embodiment, a modified M16/AR15 rifle or carbine includes a bolt having a maximum outside diameter greater than that of a standard M16/AR15 bolt; and a bolt extractor pivoted to the bolt. The bolt and the bolt extractor are operable to: transport a cartridge from a magazine to a barrel, and eject a spent cartridge from the barrel. The rifle or carbine further includes a barrel extension configured to receive the bolt; a standard M16/AR15 upper receiver coupled to the barrel extension; a standard M16/AR15 lower receiver coupled to the upper receiver.

1 . A cartridge, comprising:
 a bullet having a diameter greater than or equal to 0.224 inch; and   a case having a case head diameter greater than or equal to 0.45 inch,   wherein a length of the cartridge equal to or slightly less than 2.26 inches.   
     
     
         2 . The cartridge of  claim 1 , wherein the bullet diameter is greater than or equal to 0.243 inch and less than or equal to 0.43 inch. 
     
     
         3 . The cartridge of  claim 1 , wherein the bullet diameter is greater than or equal to 0.264 inch and less than or equal to 0.43 inch. 
     
     
         4 . The cartridge of  claim 1 , wherein the bullet diameter is greater than or equal to 0.277 inch and less than or equal to 0.43 inch. 
     
     
         5 . The cartridge of  claim 1 , wherein the case head diameter is less than or equal to 0.477 inch. 
     
     
         6 . The cartridge of  claim 1 , wherein the case head diameter is less than or equal to 0.473 inch. 
     
     
         7 . The cartridge of  claim 1 , wherein the case has a base diameter slightly less than the case head diameter. 
     
     
         8 . The cartridge of  claim 1 , wherein the case has a case length greater than or equal to 1.7 inches and less than or equal to 1.75 inches.