The Villar Perosa (officially the Revelli Modello 1915) is an Italian double barreled, pistol-calibre machine gun, often credited as the first submachine gun. It was used during World War I by the Italian Army.
The Villar Perosa was designed in 1915 as an aircraft gun by Italian engineer Bethel Abiel Revelli. It was initially manufactured by Officine di Villar Perosa, from which it took it gained its name. Production rights were also given to FIAT. As an aircraft gun it was ineffective, as it was designed to fire low-powered 9mm Glisenti ammunition, which was even weaker than dimensionally similar 9×19mm Parabellum ammunition, at the extremely high cyclic rate of 3000 rounds per minute, or 1500 rounds per minute per barrel.
The Italian Army showed some interest in the weapon and fielded it in various roles during World War I, including as a support weapon, a stationary machine gun, and a trench-clearing weapon. It was in this role that the Army decided it was most effective, and in early 1918, they sent a request to Beretta to convert the Villar Perosa into an infantry carbine. The result was the Beretta M1918.
From 1917 to 1918, the Italian government contracted a Toronto-based electrics company to manufacture Villar Perosa guns with tripod attachments.
After the war ended, the original manufacturer of the weapon, Officine di Villar Perosa, designed a single-barreled version commonly known as the OVP, which saw use in World War II.
The Villar Perosa is a double barreled submachine gun. It consists of two independent receivers joined together into a single body, each with its own firing mechanisms and separate 25-round magazines. The magazines are top-loading.
The standard version of the gun featured spade grips. Later models were sometimes fitted with wooden stocks for use as a mobile infantry weapon.
An Austro-Hungarian copy of the Villar Perosa was made in 1918, known as the Sturmpistole M.18, made by Steyr. The most notable visual difference is its straight 9mm Steyr magazines instead of the curved 9mm Glisenti magazines.
A unique variant chambered in .455 Webley Automatic was tested by the British Army in 1915, but it was not adopted.