Enhanced life barrel

Abstract

A firearm having a stock and an enhanced life barrel attached to the stock. The enhanced life barrel has a tapered bore and either parabolic or 5R rifling. The barrel includes a chamber and a throat. Each of the tapered bore, the chamber, and the throat are lapped and polished to a finish of about 15Ra of better. The enhanced life barrel includes a ferritic nitrocarburizing finish of greater than about 0.0003 inches thick.

1 . A firearm comprising:
 a stock; and   an enhanced life barrel attached to the stock; the enhanced life barrel having a tapered bore and rifling extending along at least a portion of the tapered bore, the rifling being selected from the group consisting of parabolic and 5R.   
     
     
         2 . The firearm of  claim 1 , wherein the rifling includes five lands and five grooves, each of the five lands having sides formed at an angle of about 65° to a top of the land. 
     
     
         3 . The firearm of  claim 1 , wherein the tapered bore being lapped and polished. 
     
     
         4 . The firearm of  claim 3 , wherein the lapped and polished, tapered bore has a finish of about 15 Ra of better. 
     
     
         5 . The firearm of  claim 1 , wherein the enhanced life barrel includes a chamber and a throat, each of the chamber and the throat being lapped and polished. 
     
     
         6 . The firearm of  claim 1 , wherein the enhanced life barrel includes a ferritic nitrocarburizing finish about an inside and an outside of the enhanced life barrel. 
     
     
         7 . The firearm of  claim 6 , wherein the ferritic nitrocarburizing finish having a thickness greater than about 0.0003 inches. 
     
     
         8 . A enhanced life barrel comprising:
 a tapered bore therethrough, the tapered bore being lapped to a finish of about 15Ra or better;   a parabolic rifling extending along at least a portion of the tapered bore; and   a ferritic nitrocarburizing finish about an inside and an outside of the enhanced life barrel to a depth of greater than about 0.0003 inches.   
     
     
         9 . A enhanced life barrel comprising:
 a tapered bore therethrough, the tapered bore being lapped to a finish of about 15Ra or better;   a 5R rifling extending along at least a portion of the tapered bore, the 5R rifling having five lands and five grooves; and   a ferritic nitrocarburizing finish about an inside and an outside of the enhanced life barrel to a depth of greater than about 0.0003 inches.