What was the Soviet reaction to the Sturmgewehr? EnsignExpendable, at his excellent Soviet Gun Archives blog has the answer:

“To the People’s Commissar of Defense, Marshal of the Soviet Union, comrade I.V. Stalin:

Since the Spring of this year, forces of the Kalinin, and then Volkhov and Leningrad Fronts have captured, among other weapons, several specimens of new German automatic 7.92 mm carbines, which are a new type of infantry weapon that has not been previously used by the Germans in large amounts until recently.”

And here is the Soviet intel on the gun itself (note the incorrect magazine capacity):

“Enemy tactics and technology

Engineer-Captain Ya. Krutik

1. New German handheld machinegun

The German army has recently adopted a new handheld machinegun, using an intermediate round (an average between a rifle round and a pistol round). The machinegun’s designation is “MK belash 42 (H)”. The automatic mechanism is driven by redirection of gases through an opening in the barrel.

The machinegun can fire automatically or in single shots, for which a switch is present in the trigger guard, next to the pistol grip.

The machinegun is fed with a box magazine, which holds 35-38 rounds.

• Caliber: 7.9 mm
• Length: 935 mm
• Mass: about 5 kg
• Round mass: 16.8 g
• Bullet mass: 8.2 g”

It seems their technical advisers were not ones to get excited; this sort of dry technical analysis of impressive new enemy technology is typical of Russian documents from the period.

Ensigns translations of Russian documents really are priceless to non-Russian-speaking Anglophones. Anyone interested in Soviet technology history should head on over to Soviet Gun Archives, as well as his other blog (dealing in armored fighting vehicles), Archive Awareness.