Maybe not - GT pointed out that the overall length of the cartridge is critical.
He said he has some 9mm ammo that that didn't feed properly because it was just little too long.
My guess is that the tube would load smoothly, but once you get into the drum area, the rounds would get jammed up.
The .30 cal (7.65mm x 21mm) is 2mm longer than a 9mm luger (9mm x 19mm).
See:
" AEG drum almost out flanked me!!!"
It's in the
Repairs, Restoration & Refinishing topics
Linked here:
https://forum.lugerforum.com/showthread.php?t=42149