This paper model is a simple PM M1910, a heavy machine gun used by the Imperial Russian Army during World War I and the Red Army during World War II, created by Orlik. PM M1910 was adopted in 1910 and was derived from Hiram Maxim's Maxim gun, chambered for the standard Russian 7.62x54mmR rifle cartridge.
The M1910 was mounted on a wheeled mount with a gun shield and was replaced in Soviet service by the SG-43 Goryunov which retained the wheeled and shielded carriage, starting in 1943. In addition to the main infantry version, there were aircraft mounted (PV-1) and naval variants. For more information please click here.
You can download this paper gun template here: 1910 Heavy Machine Gun Maxim PM M1910 Free Paper Model Download