My wife has an older Win 101 that has been tricked out to a trap gun. She shoots it very well. However she keeps getting misfires on the under barrel, first barrel to fire. It seems the hammer didn't cock. Ejectors on both barrels work fine when the barrels fire. I have watched and coached her to ensure she is opening and closing the gun to it's full cycle but occasionally it repeats. When I use the gun I have never encountered this problem. I am perplexed at what is the issue. I would appreciate some varied thoughts.