#rp46

Degtyaryov’s DP-28/DPM

By the mid 1920s, with the Russian Civil War over, the Soviet military recognised the need for a new indigenous light machine gun. Vasily Degtyaryov began developing a light machine gun in the early 1920s, long before the Soviet army called for a new light machine gun, the result was the DP-27.  

The design was further refined and adopted by the Soviet army in 1928, following two years of trials as the DP-28. Degtyaryov’s light machine gun was simple with early models having well under 100 parts. It used a flapper locked breech and was gas operated with a long-stroke gas piston system. It fed from a narrow 47-round pan magazine which led to its nickname 'the record player' as the magazine’s top cover rotated as the weapon fired. The magazine was his was the weakest element of the design as it was liable to damage which inevitably caused feeding issues. The magazine was cumbersome, heavy and made the gun difficult to carry when fitted. The weapon itself weighed 9kg and fired at between 500 to 600 rounds per minute.

Vasiliy Degtyarev with a DP-28 (source)

The weapon’s charging handle is beneath the receiver on the right hand side and the weapon also ejects from the bottom of the receiver. The DP had a grip safety protruding from just behind the trigger guard. Degtyaryov’s design was simple and mechanically sound. Known for its reliability, during the Winter War the the Finns used any DP-28 they could capture. However, the design had several flaws. Including weak bipod legs and a recoil spring susceptible to heat. These drawbacks became clear during the early phases of the war. 

The DP's recoil spring was initially located around the gas piston, this lead to issues with the gas tube getting hot and the spring becoming a heat sink, the spring would warp and melt and cause failures. To address this flaw the Soviets modified the DP in 1943, re-designating it the DPM. The DPM moved the recoil spring to the rear of the receiver. This necessitated a new design of stock which incorporated a pistol grip. The DPM also had an improved, stronger bipod which attached more securely to the barrel casing rather than the piston housing. This change also improved the balance and handling of the gun when firing from the bipod.

DPM (source)

The DP-28 spawned a series of variants including the DPM, the aircraft mounted DA and the armoured vehicle mounted DT and DTM. In 1946, the DP was again adapted to feed from a metallic belt as the RP-46. The belt feed allowed the RP-46 to fulfil the sustained fire role although it increased the weapon's weight to 13kg. The Soviet Union manufactured nearly 800,000 DPs and its various iterations. The DP saw continued service into the 1960s with Soviet and Combloc forces and saw action in Korea and Vietnam.  

The belt-fed RP-46 (source)

Stalin made Degtyaryov a Hero of Socialist Labour in 1940, he rose to the rank of Major General of Engineering and Artillery but died in 1949, aged 69. Degtyaryov was a prolific designer developing: the PPD-40 submachine gun, the PTRD anti-tank rifle, the ill-fated DS-39 medium machine gun, the initial design of the DShK heavy machine gun and the ubiquitous RPD light machine gun which replaced the Degtyaryov’s earlier light machine guns. DPs continue to be found in conflict zones around the world including Libya, Syria and Afghanistan

Sources:

Images: 1 2 3 4 5 6 7 8

Military Small Arms, I. Hogg & J. Weeks, (1985)

DP-28 vs DPM, ForgottenWeapons, (source)