The Soviet DShK Model 1938 heavy machine gun was developed to a Red Army requirement prior to World War 2 (1939-1945) to replace the aged Maxim Model 1910 (Soviet designation of ("PM M1910"). The newer mark proved to be the same class of weapon as the well-accepted and respected Browning M2 and equally as popular the world over. The Model 1938 served throughout World War 2 with Red Army forces and into the Cold War in a more refined, modernized form. The sheer production numbers have given the DShK series such a reach that the weapon still enjoys widespread use even today (2013).
The Soviet military understood the value of quality heavy machine guns in its arsenal even prior to World War 1 when the Maxim Model 1910 (Soviet designation of "PM M1910") was in use. These weapons were entire systems consisting of the gun with integrated cooling jacket over the barrel, a heavy duty receiver design, basic spade grips, a wheeled carriage and included armored shield for the gunnery crew. The 140lb weapon was chambered for the 7.62x54mmR cartridge and managed a rate-of-fire of 600 rounds per minute through a short-recoil, toggle-locked internal action. The type was produced from 1910 to 1939 and became a stable of Imperial Russian / Soviet military use in that span while also seeing use with the forces of the Austro-Hungarian Empire, China, Estonia, Finland, Hungary, Iran, North Korea, Mongolia, Poland, South Korea, the Ottoman Empire (Turkey) and North Vietnam in time. Production was restarted after the German invasion of the Soviet Union in 1941 and spanned from then until the end of the war in 1945.
As steady as M1910s were, they proved exceedingly limited for a Soviet military looking to streamline its mobility for a future war with one of its many neighbors. As such, a new design was sought though one with the same in-the-field robustness as the Maxim design. Origins of the DShK series lay in an early initiative that brought together the work of Vasil Degtyaryov and Georgi Shpagin, the new weapon incorporating the gas operation and locking facility developed by the former with the feed mechanism developed by the latter. The design grew into a lengthy (though lighter) weapon chambered for the large 12.7x107mm Soviet heavy machine gun cartridge operating through a rotating cylinder feed system. The rotating system stripped a cartridge from the incoming belt magazine and delivered the cartridge to the chamber ahead of the bolt. The weapon sported a rectangular receiver with dual spade grips for a firm two-hand hold. Sighting was through a basic iron arrangement affixed over the receiver and barrel. The long-running barrel was partially shrouded by a section of cooling fins giving the weapon a throwback look to machine gun designs emerging in the 1920s and early 1930s. The muzzle was capped by a noticeably large brake while the gas cylinder - which was used in the action - was fitted under the barrel. The weapon was issued atop a rather clumsy and heavy steel-framed, two-wheeled carriage with tow arm - the same cumbersome unit of the preceding M1910 mark which, once again, limited the weapon's tactical flexibility. After passing the requisite state trials prior to acceptance, the weapon was adopted and formally recognized in inventory as the "Degtyereva-Shpagina Krupnokaliberny 1938" - or "DShK Model of 1938" or "M1938" for short. The DShK series gun weighed in at 75lb compared to the 140lb unit of the PM M1910.