I had an extra shellholder which I shaved a little. Still not able to bump past a certain point. Two things happen: 1. I can tell that the shellholder is not "hitting" against the ram any longer if I go past 1/4 turn clockwise (I feel it and and don't hear the familiar sound) and 2. At this point I see a " pronounced" if you wish ring exactly where the shoulder ends and the mouth begins.