Proton mortar

The proton mortar was a type of heavy infantry weapon that saw service with the  and Marine Corps. Consisting of a metal tube with a lobbing mechanism attached to the bottom that propelled the projectile outward, it could fire 81mm  shells out to a distance of two or three kilometers both for direct and indirect fire missions. The weapon itself, along with its stand, was transportable by a single soldier, though mortars were commonly manned by two soldiers at any given time. When in combat, one soldier aimed the weapon while the other primed the shell and inserted it into the tube. If called upon to move their position, one soldier would take the launch tube and the other would take the base, sharing the burden of ammunition between them.