The 'new' dimensions of the brass will matter just as much as the quality of materials and construction (if not more with the belted 7mm Rem Mag).
Most of the Euro manufacturers will presumably be basing their cases off 'CIP' specs whereas the Americans will be going with 'SAAMI' specs.
Furthermore, the Americans are more in tune with the idea of chambering the belted magnums to headspace off the shoulder and not the belt.
Correct me if I am wrong, but I believe it is possible for a 7mm Rem Mag chambered to SAAMI specs to 'fail' on CIP gauges.
If you start out with undersize brass which headspaces off the belt, and blow it forward to the shoulder, then proceed to size it back to headspace off the belt again, you might not be getting the best out of your brass.
Not tested my ADG brass yet (my... precious!
) but have plenty of Remington and Federal to get preliminary loads established.
For the prices that CDSG are charging
for unprimed PPU :
Prvi Partizan Rifle Brass 7mm REM MAG 50 Pack C115 - CDSG Ltd , I'd much rather buy 100 rounds at just over a pound a pop from Kranks:
7mm Rem Mag PSP BT 140gr PPU Prvi Partizan Rifle Ammunition Pack 100 - Centrefire Ammunition - AMMO , fire them off and look at how the brass has fireformed.
