It probably just needs to be cleaned, but I'm asking because I have no idea. It seems like something is a little weird in the stock where it holds shells. When I pull back on the whatever to chamber another shell, it catches, keeping anything from cycling, and now it won't properly accept shells into the stock... under loading whatever, in fact scratching them pretty badly and stopping them dead right about where the brass begins. I've only put about 30 rounds through it since I got it, but I have no idea how long it's been since dad (who gave it to me) cleaned it. Do these sound like problems with a dirty gun or a malfunctioning one?