Originally Posted by Jtplumb
Never seen a bulge or split 9 inches from the muzzle unless full of mud or snow(your probably screwed if you do that with any gun anyway!). I believe Churchill cut that spot on one of his with a razor to prove little pressure out there. Always good to have a gunmaker go over your gun and advise.

9” from the muzzle is exactly where barrel specialist measure for MWT. They measure there, at that specific distance from the muzzle for a reason. It’s a crucial area. What kind of barrel work do you do?