Only once and that was on a 20 bore back action hammer gun. The gun was proofed for black powder but the barrel wall thickness was good so sent it off for nitro proof. I have sent very many similar guns for re-proof without a hitch. This one cracked at the cut off which was well radiused; bent like a banana. The barrels were fine. The gunsmith I used never liked failure so the gun was put back and the crack welded somehow; I think he called it stainless steel welding. Anyway the repair is all but invisible except on very close inspection. Gun re-submitted and passed fine. I undersatnd that such things are quite rare except on earlier breech loaders with sharp cut offs. I have no intention of ever selling the gun in question but reserve it for my own use knowing the history but there is no reason why it should ever fail in normal use. Lagopus.....
