I was gives 900+ rounds of once fires 9mm brass from an FBI Range Session. The brass has the primers crimped in place.
The brass is marked:
93
WCC
There is also a Circle with a cross inside, on the rim as well as the other identification mentioned above.
I'm guessing Winchester military.
Maybe even NATO and/or Machine Gun Ammo.
All rounds were fired in fully automatic weapons.
Thanks - J.Solo