Ever seen a pair of forcing "steps"? Sharp, abrupt halt of the chamber area, typically on older guns, likely intended for use with roll crimped, paper rounds.

I've had one set of those worked on. Both barrels were choked full and full, and the choke was let out as well. I probably wouldn't do it to a more modern gun, but, the old girl throws very uniform hunting patterns today, versus the dense, splotchy patterns previous. It works well with either plastic wads or fiber wads, from my limited testing.


Best,
Ted