The other day, I bought a Remington 870 Express. It has never been shot and I was planning on shooting it yesterday. Well, I pumped it without a shell in it. When I pumped it, The slide stopped in the middle. From what it looks like, the bolt carrier has a notch in it that slides in a groove that goes up and down the barrel, well it looks like the bolt carrier came out of that groove just a little bit. The bolt carrier wont move so I cant get it back in that notch and the slide release is jammed. Does anybody know how this can be fixed?