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You know, Jim - I missed the "7.65" in the OP's heading.
Nice catch.......
But the only 7.65mm non-carbine (carbines were 11-3/4") bbl I can recall is from the 1920 Long Barrel Commercial Models, which were supposed to be anywhere from 10"-20" long - so maybe a custom shortening ?
A few pics would be nice, especially of the muzzle end of the bbl. (Presuming the barrel length was measured correctly/internally via a rod dropped downbore against the closed breech)
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