Is it an express or a Wingmaster? Remington choke designations ARE near the receiver. If the barrel is a vent-rib barrel and a glossy finish, it's a Wingmaster. If it's got a matte finish, it's quite likely an express. If it's stainless, it's a Marine Magnum. If it's an express or marine, it's probably either cyl or imp, and you're good to go. If it's a Wingmaster, it's either a fixed choke or has the Rem Choke system. My Wingmaster is a MOD, so I can't do slugs. My Winchester model 1897 is a riot gun and has a CYL bore, so it's my slug gun.To make this easier (maybe) I asked my friend what kind of a shotgun he has - sorry I didn't think to ask him before. He has a Remington 870. Does this shotgun have the type of barrel that you can shoot slugs with?