Sorry I didn't take any photos of the cases, but I've been running some Bulgarian surplus 5.45 through my SAR-2 and last weekend I noticed that the primers were looking pretty cratered where it looked like the metal of the primer was trying to flow back into the firing pin hole in the bolt.
I don't know how this rifle was treated before I got it, but it looked about as new as an SAR-2 ever looks. I've only run about 1500 rds of this Bulgy surplus through it and never noticed anything strange, but then I wasn't really looking.
Is it common for these things to have headspace issues? Or does this Bulgarian ammo have a reputation for having really soft primers?