M1922 CAVALRY MACHINE RIFLE
Before the First World War the US Army’s cavalry had been equipped with the M1909 Benét–Mercié Machine Rifle, Caliber .30. With the Army’s adoption of John Browning’s M1918 Automatic Rifle during the war the US Cavalry called for an improved, dedicated cavalry model of the BAR.
The Army sought a improvements to the BAR’s accuracy and a compromise between portability of a light, shoulder weapon and the sustained fire ability of a machine gun. A demand emerged for a specialised cavalry automatic rifle and during the early 1920s the Ordnance Department began modifying the M1918. In February 1920, the Infantry and Cavalry Board made an official request for a modified BAR that could act as a cavalry-deployable light machine gun. The short-lived Model 1919 was the first of these experiments to emerge followed by the transitional Model 1920. Finally, the M1922 Cavalry Machine Rifle was introduced. One of the few remaining examples is held by the Springfield Armory Museum, its records apparently note that John Browning himself put 5,000 rounds through the gun during development testing.
An M1922 with its spare parts and ammunition mounted on a horse (source)
The M1922 Cavalry Machine Rifle differed from the M1918 BAR in a number of ways. The change included a new heavier, finned barrel, a shorter forearm with an additional wooden hand guard on the top of the barrel. The addition of a non-adjustable bipod with spiked feet. A detachable mono-pod was also added to the buttstock. With these additions the BAR’s weight rose from 7kg (15.5lb) to 9.1kg (20lb). As a result the ‘M1 Machine Rifle Hanger’ was developed for pack horses which weighed 30kg (66lbs) and included an M1922, four 300 round metal ammunition boxes and a set of spares.
In reality the BAR could never meet the unrealistic requirement of a light machine gun capable of sustained fire. With the US’ entry into the Second World War very few of the original M1918, M1918A1, M1922s survived the program to upgrade the US military’s BAR inventory to the M1918A2.