I bought a Remington 11-87 super mag (full camo) last year brand new. I picked it up the other day and noticed the stock was loose. I can twist it back and forth. I took off the butt plate to tighten it up, but i can't seem to figure out how to get it tight. There seems to be a hollowed out nut with a pin through it. Does anyone know how to tighen these up? I don't really want to take it back where I got it, they would probably have it to long, and I need it to throw buckshot for the next three weeks.