Ran into an odd problem. Picked up a replacement barrel for a customer's gun and the thing won't screw in. Lacks about .030 of the extention touching the frame 'cause the barrel is already touching the headspace ring. I know I can get shims to set back the extension (if I can get it loose) but it appears to me that the front sight might be enough out of line to be noticeable. Any opinions on the idea of chucking the barrel in the lathe and facing off the rear enough to get the threads of the bushing to engage and the extension to contact the frame as it should?