Gun Barrel Refurbishing Using a Shrink-Fitted Autofrettaged Liner

Abstract

During the firing of guns, the barrel undergoes two major damaging processes: wear of its inner surface, and internal cracking. Barrel’s are condemned based either on the increase of their internal diameter due to wear, or the severity of their internal cracking. The cost of replacing such a damaged gun barrel runs in the tenth of thousand of US$. Therefore, cost effective methods are sought for restoring such gun barrels. In the present analysis a new method is proposed for refurbishing vintage gun barrels by machining their inner damaged layer and replacing it by an intact, autofrettaged, shrink-fit liner that will restore the barrel to its original performance. The preliminary results demonstrate the ability of this process to mend such barrels, bringing them back to their initial Safe Maximum Pressure (SMP) and their intact conditions, rather than condemning them. Furthermore, such an alternative seems to be cost effective.