While the Degtyarev DP series of light machine guns proved a highly serviceable suppression weapon in its position among the standard Soviet infantry squad during World War 2, it was rooted in the 1928 and not without some inherent shortcomings achieved in a design developed during peacetime. When the German Army invaded the Soviet Union through Operation Barbarossa, it served to showcase the limitations of the DP through rigorous usage. Regardless, the Red Army was reeling from defeat after defeat and any serviceable automatic weapon of note was placed into Red Army soldier hands.
The original DP models held two distinct weaknesses in their design. One lay in the rather fragile construction of the bipod which was prone to fractures and breakages in the heat of battle. The loss of the bipod limited proper handling and stability during firing until it could be repaired or replaced. The other drawback was in the internal return spring used in the gas-operated action which tended to warp due to the heat buildup caused by the barrel through heavy, repetitive firing. Work, therefore, began on an improved version of the weapon which were first made available in the campaigns of 1943-1944, ultimately becoming the mainstay Red Army light machine gun in 1945 - the final year of the war. The new "modernized" form was known under the designation of "DPM" to signify their modernized revision and changes included a heftier bipod assembly as well as a relocated return spring. The return spring was now fitted to the aft portion of the bolt which required the recoil spring tube to extend out over the rear of the receiver. This, in turn, prevented use of the original rifle-style grip handle seen in the DP. Instead, a conventional (though somewhat crude), stand-alone pistol grip was added which undoubtedly gave a better, more natural feel. A simpler shoulder stock was added. Beyond these changes, a new safety was introduced as well, doing away with the grip safety of old. Once in service, the DPM gave a good account of itself and was put to the test in the bloody Soviet offensives that ultimately drove the German Army back to Berlin. The wide ranging tank and artillery battles across expansive battlefields had now given way to bloody house-to-house fighting, spilling out into the streets of the German capital itself.
All other services of the DPM remained faithful to the original DP model. The type still fired the same 7.62x54mmR cartridge from a gas-operated action (the gas cylinder fitted under the barrel). The weapon was fed from a 47-round "pan" magazine mounted along the forward top of the receiver - reloading was still cumbersome and time consuming. The cyclic rate-of-fire was 520 to 580 rounds per minute with a 2,770 muzzle velocity reported. Overall, the Red Army machine gunner found the changes quite suitable for the modernization made for a more accurate and easier-to-handle automatic weapon system. The DPM continued in service with the Soviet military up until the 1960s when it was itself replaced by the newer, more modern, PK series of light machine guns.
Chinese military industry took on local production of the DPM as the "Type 53" and these saw longer use as frontline weapons than their Soviet counterparts.
DPM machine guns were also modified as tank machine guns in the DTM series. The weapon was fed by a 60-round pan magazine and general retained the consistent look of the DP/DPM series. The DTM replaced the outgoing DT tank machine guns in similar fashion.