I am having really bad problems with my Remington 870 supermagnum express. I bought this gun last year during a Black Friday sale so i could use it for duck hunting the following year. Last week and this week when I was duck hunting the gun could not load 3 inch shells into the chamber. I load the shells into the magazine and when I pump the shotgun it gets jammed and is not able to go into the chamber. I have tried 4 different brands of 3 inch shells including, hevi steel, hevi metal, Kent, and black cloud. Every single shell gets jammed when I try to pump the shotgun. For deer season a couple weekends ago I also used 3 inch federal slugs and they also jammed. I have used 2,3/4 shells and they seem to work fine. Occasionally they fail to eject from the chamber. I'm pretty disappointed with my gun right now and could use some help. It's really frustrating when my gun jams when I'm trying to hunt ducks. It's not the shells because my friends all use benelli shotguns and the shells do not jam in their gun. Thinking about just getting rid of the gun because it's not even worth selling at half price