The MG 37(t) was another original czechoslovakian design; this heavy machine gun originally carried the designation ZB 1937. It was the answer to the already failed quest of the czech military during the 1920ies for a heavy machine gun. In early 1930 Václav Holek and Miloslav Rolcik started development of a heavy machine gun that after several modifications resulted in the heavy machine gun ZB 1935 that showed itself vastly superior to the WW I - era Schwarzlose machine guns then still in use.
The weapon was built in a limited series and also bought by Great Britain, which manufactured it under license by BSA Ltd and under the designation BESA machine gun for use as a vehicle-mounted machinegun for tanks. An intersting fact is that because the BESA was identical to the czech origin, both were in the 7.92mm Mauser caliber. Because the british armor wanted the BESA, but the BESA could not be converted to fire the british .303 ammunition, and because the infantry did not want to switch over all their Enfields to the german caliber, the tankers were granted an exception and even had their own special manufacturing plant in england for producing the german ammunition type.
Of the czech ZB 1935 287 were sold to romania; the weapon was further improved and standardized as the heavy mg for the czech military under the designation ZB 1937. Few weapons had been built before the germans occupied czechoslovakia, most of which were exported to other countries, e.g. romania bought another 8,000 ZB 1937. About 12,000 were built by the czech weapon company in Brno for international custiomers and another 6,000 for the czech military.
The weapon was integrated into german army use under the designation MG 37(t) and production was continued until 1942, when production was switched over to producing parts for german weapon designs. Until then, another 6,411 weapons had been built for the SS.
The MG 37(t) is air-cooled and gas pressure - operated; when firing the barrel (together with the locked breech block) is recoiling about 2cm, then the bullet passes the gas valve and the gas pressure unlocks the breech from the barrel for the further recoil. The weapon is belt-fed with metal ammunition belts feeding 7.92mm Mauser ammunition from the right side. The ammunition belts by default came in 100-round (weighing 3.4kg) and 200-round (weighing 6.8 kg) lengths but could be linked endlessly.
A light and a heavy barrel were available, the heavy barrel is recognizable by the distinctive cooling gills around the barrel. The weapon had a regulator for the amount of extracted gas pressure from the gas valve on the barrel. The rate of fire could be increased by the switch of a special accelerator from 500 to 700 rounds per minute.
A distinct disadvantage of this weapon was the tedious procedure when changing the barrel. The sights range from 200 to 2,500 meters. Other data: length 109.5cm, barrel length 73cm, weight (empty) 19kg, weight (empty with tripod) 36.5kg, V0 = 790 m/s.