It's possible that a "G" date receiver (kept in inventory for a period of time) was used in a Mauser commercial Luger. If so, some of those were ordered in 7.65mm / .30 Luger.
I have a 1938 receiver that is on a commercial Mauser in the "u" block.
Is there a military concealment code toggle, or commercial Mauser banner toggle on the pistol?
But, if you put 9mm Luger rounds through it, it's a 9mm Luger caliber gun.
Check out our FAQ PDF for lots of reference info. Follow the FAQ link at the top of every forum page. The price is right. It's free to download.
John Walter's book on t
he Luger Story is a good intro. If you want details, get
Geoff Sturgess' book.
Marc
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