in the left barrel of a new to me, Win 21, made in 1956. Appears to be in excellent condition. Two theories offered by friends with 21's are, 1. chamber rims cut a fraction too deep, 2. Spring is not as strong as it should be. I am reloading W AA's using cheddite primers. I pulled triggers on a block of wood and both left and right firing pins protrude about the same distance, farther than the thickness of a dime. I haven't yet but plan to try other brands of shells and keep track if it is only reloads or does it happen with new shells. Open to other suggestions.
