So, my BIL shoots a 300 RUM. I shoot a 6.5-284. We generally always go to the range together. Both of our rifles are threaded to shoot suppressed. My suppressor is the 338 variety so that I can use it on any weapon. I have no problems on my rifle. On his there are baffle strikes near the end of the suppressor on every shot. I take it off and put if on my other buddy's rifle (.308) and he has no trouble, shoots clean. Put it back on the RUM and it strikes again. So, its obvious to me that his threads are off....right? I take the rifle to our smith. He puts it on the dial indicator and says its within tolerance. At this point I am left with 2 other thoughts: My smith is full of bs or he has a pressure problem. He is shooting an Obermeyer undersized bore. Could this have anything to do with it?? Has anyone experienced this?