I have a AR-9 and would like to shoot a 147 gr cast bullet. They will not freely chamber unless seated very deep. So deep that some brands of brass will bulge the mid section. Obviously a less than desirable situation, the best answer was to simply deepen the throat.
I'm a little bit handy with tools, so I rented a 9mm throating reamer. It came with warnings about super hardened steel in some 9mm barrels. Well mine is one of the super hard kind, and the reamer wouldn't do so much as put a scratch in it.
Are there other options for throating these barrels?