I spoke with one of the men who oversaw these projects, M101 and 23. He told me the following. "The M101 and M23 were both designed and manufactured by Olin Kodensha Japan. There was not a single individuals name associated with the design of either gun. It was the result of a group effort."
He also debunked the Herb Orre theory of the M21. He told me "The model numbers were either associated with the year of manufacture or tied to project numbers in the Design Dept."

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