A semi-automatic shotgun is a repeating shotgun with a semi-automatic action, i.e. capable of automatically chambering a new shell after each firing, but requires individual trigger-pull to manually actuate each shot. Semi-automatic shotguns use gas-, blowback or recoil operation to cycle the action, eject the empty shell, and load another round. Many semi-automatic shotguns also provide an optional manual means of operation such as by pump action or a charging handle.