I bought a new Mossberg 930 waterfowl last month to duck hunt with. I mopped out the barrel to make sure it did not have any grease in it, took it hunting the next day and it failed to cycle after second shot on a group of ducks. The shell coming out of the magazine tube jammed with about 1/2 inch of the base of the shell sticking out of the tube. The fired case ejected just fine and the bolt locked back. When I got home I thoroughly cleaned the gun according to the video by Jerry Miculek. Took it back out and the same thing happened. I then tried leaving a thin film of oil on the piston, still had the same problem. I have cleaned the piston, piston rings and groves, magazine tube and all receiver parts and bolt. Nothing helped. Also, it cycles just fine by hand. I am sending it back to Mossberg for repair. Any body have the same problem? Any idea what to expect from Mossberg?