Years ago Wallace Gusler pointed out the concept of a "smooth rifle", which was a rifle-like gun built with a smooth bore. His point was that not every rifle-like gun with a smooth bore is just a rifled gun that later got bored out when the rifling wore out. Some were built with a smooth bore. He was describing pieces which, architecturally, were more like rifles, in that they were built with cheek pieces, grip rails, a rear sight, sometimes a box. These details contrast with the stereotypical architecture of fowlers.