This is the World War 2 German Army MG-42 Machine Gun Firing Demonstration at Dellwood Park in Lockport, Illinois on 8 September 2013, by 5th Company GrossDeutschland.
The MG 42 (shortened from German: Maschinengewehr 42, or “machine gun 42”) is a 7.92×57mm Mauser general purpose machine gun designed in Germany and used extensively by the Wehrmacht and the Waffen-SS during the second half of World War II. It was intended to replace the earlier MG 34, which was more expensive and took much longer to produce, but in the event, both weapons were produced until the end of the war.
The MG 42 has a proven record of reliability, durability, simplicity, and ease of operation, but is most notable for its ability to produce a high volume of suppressive fire. The MG 42 had one of the highest average cyclic rates of any single-barreled man-portable machine gun: between 1,200 and 1,500 rpm, resulting in a distinctive muzzle report.
The MG 42’s high rate of fire resulted from analysis which concluded that since a soldier typically only has a short period of time to shoot at an enemy soldier, and muzzle rise quickly threw initial aim off, it was imperative to fire the highest number of bullets possible in the shortest time possible to increase the likelihood of a hit before the recoil overcame the inertia of the gun and pushed the aiming point upwards. The disadvantage was that the weapon consumed exorbitant amounts of ammunition and quickly overheated its barrel, making sustained fire problematic.
Thus, while individual bursts left the weapon as highly concentrated fire at 1,200 rounds per minute, the Handbook of the German Army (1940) forbade the firing of more than 250 rounds in a single burst and indicated a sustained rate of no more than 300–350 rounds per minute to minimize barrel wear and overheating, although the excellent quick-change barrel design helped a great deal. Burst limits are typical on non-water-cooled automatic weapons, and slower-firing Allied guns such as the M1919 also had limits; they fired at a slower rate, but lacked a quick-change barrel, and so the operator had to limit his fire to a few hundred rounds per minute to allow the barrel to cool between bursts.
Due to the slower firing rate, this led to a longer period of time spent shooting, but a roughly equivalent total number of rounds fired. Operationally, the MG 42’s main drawback was that it could consume ammunition at such a high rate that it was very difficult to keep one firing during offensive actions, because ammunition had to be carried forward on a continuous basis. This was also a problem at the end of the war with inexperienced German troops, good fire discipline was a must and the level of training that the German infantry was receiving was poor.