Well, with one day left for Duck Season. I went and bought a new shotgun. I have been wanting a 3 1/2 12 guage for several years and I finally found one to make mine. This morning, the fog was heavy and the wood ducks were whistling. But my NEW shotgun was jammed. One 3 1/2 shell and then nothing. After some serious persuading!!! The fired round came free from the chamber and I went on. After a few more ducks and some more single shot cussing. I went to the shop for a little Rem Oil. All seemed well for the remainder of the morning. Tonight, I was standing in waist deep water with Mallards overhead and the problem returned. What makes my headhurt, is that the shotgun will fire five or six rounds without failure, then it would snag on two or three rounds. I tried several different shells and had the same result.] After a long story, does anyone have any suggestions? It appears the chamber is a little tight and when the shotshell expands after firing, it get hung. I cleaned the shotgun tonight and did not feel any burrs or machine marks to account for this problem.