The 75mm Pack Howitzer M116 was designed in the United States in 1920s to meet a need for an artillery piece that could be moved across difficult terrain. The gun and carriage was designed so that it could be broken down into several pieces to be carried by pack animals. The gun saw combat in Second World War with the US Army (primarily used by airborne units), with US Marine Corps, and was also supplied to foreign forces.
The howitzer M116 consisted of tube and breech, which were joined together by interrupted threads, allowing for quick assembly and disassembly. One eighth of a turn was required to connect or disconnect tube and breech. The tube had uniform, right hand rifling with one turn in 20 calibers. The breech was of horizontal sliding block type, with continuous-pull firing mechanism. The recoil system was hydropneumatic. Both recoil buffer and recuperator were located under the barrel.
In the Second World War era US Army, 75 mm howitzers were issued to airborne and mountain units. An airborne division, according to the organization of February 1944, had three 75 mm howitzer battalions – two glider field artillery battalions (two six-gun batteries each) and one parachute field artillery battalion (three four-gun batteries), in total 36 pieces per division. In December 1944, new Tables of Organization and Equipment increased the divisional firepower to 60 75 mm howitzers. The only mountain division formed, the 10th, had three 75 mm howitzer battalions, 12 pieces each. The gun was also used by some separate field artillery battalions.
