Just got a Mossburg 500 Slugster from my dad, he gave it to me. He bought it in a package deal from a pawn shop. Paid $400 for this gun, a generic (can't remember the name) USA made 20 gauge that looks very similar to a Mossburg, and a Savage 110 30-06. He got a steal of a deal, the pawn shop just wanted them gone. My Mossburg is a 12 gauge with a 24 inch barrel. I own several different actions of shotguns, this is my first pump. Anything I need to know about this gun?