Just got my steel PRI .936 gas block. Wouldn't go over the barrel shoulder on the test fit. Calipers revealed that the barrel is actually .941, so I need to remove .005 from the inside of the block. I tried a brake cylinder hone ... all it did was polish it up slicker 'n Owl Poop. Any suggestions for a way to get this done without resorting to machining? Thanks guys.
