Re: HXP Brass for reloading
The best brass you can get for reloading a Garand is original Lake City 30-06 military surplus stuff. This is often availble from the CMP at pretty reasonable prices. The absolute best stuff is LC Match brass, since you don't need to fiddle with the primer pockets. This, however, has become fairly rare.
I'd avoid the Greek surplus stuff like the plague. The CMP issued this stuff at the Nationals for the Garand and Springfield Matches a couple years ago and we had no end of problems. Very high pressure signs in the M1903s, extraction problems, and as I recall, broke a few extractors on the M1s. I doubt that this was the same production as the lot you're looking at now, since I'm pretty sure that stuff used brass cases, but it's something to be aware of. I'd also be concerned with the possibility of corrosive primers (depending on when this stuff was made), and have no idea when Greece made the switch from corrosive to non-corrosive priming.
Even good commercial brass is a great value compared to what headaches you're dabbling with by using steel cases. They weren't meant for reloading, lack the proper characteristics that makes brass the metal of choice for cartridge cases. They were nothing but a low cost war-time expediant for brass, and should be relegated to cartridge collections for their historical interest.