I thought we stole most of our sound barrier stuff from the Brits, just like we adopted their implosion calculations for Fat Man. The rest of the Moon program, as you rightly note, was Werner and crowd -- who actually bothered to read Goddard, unlike most of the U.S. establishment prior to the V2.
Frags:
There are simply too many antecedent concepts from too many directions, ALL of which went into Kalash's development of the AK-47. Significant direct German involvement is unlikely because of timing (indirect plenty of course based on captures). While the weapon was adopted in 1947, that was following nearly 2.5 years of development, trials, and provings. German weapons design was certainly one influence, but by no means the only one.
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