Designed by Hiram Maxim, the maxim gun was water-cooled, by a jacket around the barrel that held about a gallon of water, and ammo was supplied but a fabric belt which held the ammunition. The gas produced by the explosion of the powder in each cartridge itself generated a recoil which served to continuously operate the gun's mechanism causing it to need no external power. All of it would be mounted on a sledge. The gun weighed between 40-60kg (88-132lbs) making the operation of it require a four to six man team. Hiram decided to show his invention to the British Army and in 1887 his gun was test. Although the gun passed all tests the British government did not allow use of the gun, however; later that year the gun was demonstrated to the German Army and was then authorized for use. Later on the Maschinengewehr, Vickers and Pulemyot Maxima guns were made all based on the design of the Maxim gun.
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