I think I found the fix. The chamber just needs to be brushed with a brass brush on a drill. I was considering trying to polish it with a dremel tool, but that may not be necessary. Thanks for the reply.
You mentioned a day or so ago about having trouble with an 870 super mag. In the same thread someone described spent shells stuck in the chamber. Is that what happened to yours? Mine hung up twice this morning. It has not had many rounds through it. If that's what yours was doing, what was the fix? Love the gun, just need to get this straightened out. I have a 20 ga 870 wingmaster that has seen considerable use. I don't recall ever having a problem of any sort with it.