I once had an Ithaca Deerslayer with 20" barrel (smoothbore), and with one particular lot of Remington Foster-type slugs, it would shoot 3" three-shot groups @ 100 yards. But, I have three round-ball muzzleloaders that shoot 1" or less (5 shots) @ 100yards...but only on a calm day! Are slug shotguns more accurate than muzzleloaders?? Not if you have a well-made muzzleloader, and are firing the right bullets with the correct powder charge in it!!