"Report #405
Small Arms Scientific Research Proving Grounds
December 17th, 1941
Shurovo, Moscow oblast
RE: trials of foreign submachineguns in comparison with the domestic model 1940 submachinegun and model 1941 submachinegun
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The trigger mechanism of the Schmeisser submachinegun (see diagram) consists of 12 parts in a complex arrangement, and in addition has 6 small springs. Its positive sides include a good ratio of the sear shoulders, which allows the effort on the trigger to be low.
This mechanism of the safety and fire selector is needlessly complicated. In addition, a large amount of small springs (6) makes it unreliable in its function.
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The trigger mechanism of the Schmeisser submachinegun is a good example of how not to design trigger mechanisms with fire selectors."