From what I understand, the Yugo stuff is M67 ball. Wolf has the same type large air space in it as M67. I once sliced a Wolf FMJ projectile and a Uly FMJ projectile. The Wolf had a much larger airspace than the Uly. I would bet the Wolf FMJ is pretty much identical to typical 7.62x39 military ball ammo.
What makes good SHTF ammo anyway? To me, it's ability to hold performance despite being stored for long periods of time is FAR mor important than terminal performance would be. I think for almost every circumstance, the terminal performance of the ammo in question will make little or no difference. It's about placement, and in the end, just plain hitting the guy. Even if you hit the guy in the foot, I'll bet he's not going to steal/rape/kill your whatever - he'll drop.