I have a pistol, and had it hang up, just like you describe. I moved the flints, I changed the flints, and was about to give up, when I tried a cut or sawn flint. The problem went away. Perhaps there are other changes that I overlooked but the sawn flint seems to be working. Somehow, I can't duplicate, a knapped flint to make it shoot reliably, so for now, I'll stick with the sawn flint.