RPD Machine Gun

Origins

During the Second World War the Soviet Union developed a new cartridge, the 7.62x39 mm M43. It was shorter and less powerful than the full-sized rifle round but far more powerful than the pistol ammunition of submachine guns. Soviet planners wanted a family of infantry weapons built around it: a self-loading carbine, an automatic rifle and a light machine gun. The carbine became the SKS and the automatic rifle became the AK-47. The machine gun was the work of Vasily Degtyaryov, whose pan-fed Degtyaryov DP-27 had been the Red Army's squad machine gun throughout the war. His design was selected in 1944 and named the RPD, for Ruchnoy Pulemyot Degtyaryova, or Degtyaryov hand-held machine gun. The war ended before it could be produced in quantity, and it did not reach the troops in large numbers until the early 1950s.

Design & Construction

The RPD is gas operated. A long-stroke piston under the barrel drives the bolt carrier, and the bolt is locked by two hinged flaps that are forced outward into recesses in the receiver, a system carried over from Degtyaryov's earlier guns. It fires from an open bolt and is automatic only, at a cyclic rate of roughly 650 to 750 rounds a minute.

Ammunition is held in a non-disintegrating metal belt of 100 rounds, made up of two 50-round sections joined together. The belt is coiled inside a round sheet-metal drum that clips under the receiver, so the gunner can move and fire without a loose belt trailing behind him. The drum is only a container; the gun's own feed mechanism pulls the belt through. The RPD has a wooden butt and pistol grip, a folding bipod near the muzzle and a carrying sling. Empty, it weighs about 7.4 kg, much less than the belt-fed machine guns that armies of the time issued at company level.

The barrel is fixed and cannot be changed in the field, so gunners were trained to fire in short bursts to avoid overheating. A gas regulator with three settings let the gunner increase the power of the action as the weapon became fouled. Several small improvements were made during production, including a folding, non-reciprocating cocking handle and a dust cover for the feed opening.

Combat Use

The RPD was issued one to each Soviet rifle squad. It was supplied to Warsaw Pact armies and to Soviet allies and clients in Asia, Africa and the Middle East. China manufactured it as the Type 56 light machine gun and later the improved Type 56-1, and North Korea made it as the Type 62.

It is best known from the Vietnam War. Chinese and Soviet RPDs were the usual squad machine gun of the People's Army of Vietnam and of Viet Cong main force units, working alongside the AK-47 and the RPG-2. American soldiers met it in their first large battle with North Vietnamese regulars, the Battle of Ia Drang in November 1965, and it was used in the street fighting of the Battle of Huế in 1968. Because it was light enough to carry in an assault, North Vietnamese infantry could bring automatic fire forward with their leading squads.

American reconnaissance teams of the Studies and Observations Group sometimes carried captured RPDs on missions into Laos and Cambodia. Some cut the barrel down to make the gun shorter and lighter. They valued it because it was compact for a belt-fed weapon and because its sound did not give away an American team in enemy-held country. The RPD also saw wide use in African wars, including the Rhodesian Bush War, where both guerrillas and Rhodesian troops used it.

Legacy

In Soviet service the RPD was replaced from the early 1960s by the RPK, a heavy-barreled version of the Kalashnikov rifle that shared the rifle's magazines and most of its parts. The RPK was simpler to make and to train on, though it gave up the RPD's belt feed. The heavier belt-fed role passed to the PK Machine Gun, which fires a full-power rifle cartridge. Large stocks of RPDs and their Chinese copies were passed on to allied states and irregular forces, and the gun has continued to appear in wars in Africa, the Middle East and Asia. The idea of a light belt-fed squad weapon firing the same cartridge as the rifle returned in the West decades later with the M249 Squad Automatic Weapon.