The German Gustloff Barnitzke light machine gun. Derived from the MG 42 by Karl Barnitzke, the weapon used an unusual delayed blowback action consisting of two flywheels in a rack and pinion arrangement. The flywheels were exposed to dust and mud, and were overcomplicated in design, and the gun remained a prototype only
The information on this gun is really really scarce, the only thing known about it is that it’s a prototype. It is a delayed blowback machine gun and to quote “during firing the bolt opening is delayed by the rotational inertia of two flywheels, which are driven by a rack and pinion arrangement on the bolt carrier”. Though similar to the MG-42 it was supposed to replace, its internal design differed greatly and the complexity of this weapon possibly led to no further development after WW2.
Other Rare MGs Mauser LMG Modell 1934, Wollmer LMG Modell 1926, Gustloff Barnitzke LMG, MG-131 Ground Version
During the war a number of companies produced the MG 42, although never in the numbers needed to keep up with the ever increasing demand. These included Gustloff-Werke in Suhl, Mauser AG-Werke in Borsigwald, Steyr in Vienna, Grossfuss in Dobeln, and Maget in Among them, 129 MG 42s were made each day from 1942 through 1945. More than 400,000 units were produced (17,915 in 1942,116,725 in 1943, 211,806 in 1944, and 61,877 in 1945).