I've shot rifled slugs (Winchester 1 oz. Super-X) out of my870 Wingmaster 12 ga. and consistently hit pie plates out to about 85 yards. It came with a fixed improved cylinder choke and a front bead. My grandpa has taken quite a few deer with the same gun and setup.

You can also buy a replacement rifled barrel with rifle sights or a cantilever mount toshoot sabot slugs. I put one on the same 870 and sighted it in for 100 yards with a Nikon ProStaff 2-7x32 shotgun scope.