The Hotchkissgun can refer to different products of the Hotchkiss arms company starting in the late 19th century. It usually refers to the 1.65-inch light mountain gun; there were also a navy and a 3-inch Hotchkiss guns. The 42 mm gun was intended to be mounted on a light carriage or packed on two mules to accompany a troop of cavalry or an army travelling in rough country.
The term "Hotchkiss gun" also refers to the Hotchkiss revolving cannon, a rotating barrel weapon invented in 1872 by Benjamin B. Hotchkiss, founder of Hotchkiss & Co. Though superficially resembling a Gatling gun the internals are very different, having only one firing pin rather than a firing mechanism for every barrel. It was a built-up, rifled, rapid-fire gun of oil-tempered steel, having a rectangular breechblock which moved in a mortise cut completely through the jacket. It was designed to be light enough to travel with cavalry, and had an effective range beyond that of rifled small-arms. The 1-pounder revolving Hotchkiss cannon had five 37 mm barrels, and was capable of firing 68 rounds per minute with an accuracy range of. Each feed magazine held ten rounds and weighed approximately 18 pounds. Besides the field gun version, several other versions of the 37mm Hotchkiss revolving cannon were in existence, notably versions for naval defense against torpedo boats as well as fortress versions firing shrapnel or canister shells for the defense of moats. The naval version was adopted by Russia and the United States, amongst others. The field cannon version was accompanied by a horse-drawn ammunition limber, which held 110 rounds plus six loaded magazines, totaling 170 rounds. One example is on display at the Museum of the History of the Brazilian Army at Fort Copacabana, Rio de Janeiro. A 3-pounder 47mm Hotchkiss revolver cannon was also adopted by the US and Russian navies in the 1880s. This had five barrels. With 3-pounder and 1-pounder weapons, it is difficult to determine from references what type of weapons a particular ship had. Single-shot, revolver cannon, and Maxim-Nordenfelt1-pounder cannon weapons were all used on new warships 1880-1910. All of these were called quick-firing or, in the US, rapid-firing.
Other guns
Hotchkiss also produced a range of light naval guns and, in the 1930s, anti-tank guns. The naval guns which originated in the 1880s were mostly 3 pounders and 6 pounders and originally were widely used for close-up defence of major warships against small craft armed with the newly invented locomotive torpedo. When improvements in torpedo range made them obsolete in this role, they continued to be used as small-craft armament up to and including World War II. In World War I the British motor gunboats which won naval supremacy from the Germans on Lake Tanganyika were armed with the Hotchkiss 3 pounder. The Hotchkiss 6 pounder was adopted by the British army for the first tanks. During World War II the 6 pounder was the main weapon of the early units of the numerous and successful Fairmile DMotor Torpedo Boats of the Royal Navy, not being entirely replaced by more modern weapons until 1945.