Serk, I hope you see this because I'll delete this tomarrow. You were right 7.62x39. I stopped at a place today that likes to sell assault type stuff. The case that looks like copper is brass. Thanks
Ah, cool. I was close but a bit off. 7.62x39 is a low powered rifle round, 7.62 Tokarev is a pistol round, but both from the Eastern Bloc...
7.62x39 is the cartridge most SKS and AK47s fire.
7.62x39 on the left, 7.62 Tokarev on the right:

And as Jess says, that coating is common of com bloc ammo.