Abstract: A semiautomatic gun which can be used to fire two types of ammunition comprises first and second bolts and a selector assembly operated by a user of the gun. The selector assembly selectively permits loading and firing of one type of ammunition. The gun has only a single trigger for firing either of the bolts selected by the selector assembly and the gun may be a combination of a shotgun and rifle or any other desired configuration. Each of the bolts are movable in a forward and rearward direction when fired and have bolt lock-up bearings for preventing such movement at other times. A reciprocable forestock is provided with a forestock lock release. The forestock can be pumped by the operator to initially load a round of ammunition into the chamber selected by the selector assembly.