My father works for a cement quarry and they had an 8 guage shotgun mounted on a stand that was used for busting "klinker" off the sides of the kilns. The cement dust would mix with moisture and form on the walls making it like cement, the shotgun was the only way to break it up. My dad used to bring home some of the shells (they were 4" long) and cut the solid lead slug out of them and melt them down to cast his muzzleloader bullets. Ill have to ask him if they still have it.