Most 18" barreled shotguns are 6+1, as is mine. Any larger a capacity and the magazine tube protrudes out farther than the barrel. 7 rounds is hardly any different than 8, and the 8 rounders can only hold 7, 3" mag shells in the gun anyway, same as the 18"ers, which can also hold 7 shells, regaurdless of their length. It really isn't that much of a difference.