Just picked up a police trade in remington 1100 with ribbed barrel. The guy at the counter told me the barrel had been cut off with a hacksaw. I thought he was joking. There is a burr on the inside of the barrel that could cut you. I'm wondering if this has ever been shot. Anyway I thought it might be a good idea to get a screw in choke installed. I know zip about this. I would like to be able to shoot slugs through this as well. Any recommendations on where to send it?