I had a bad experience with Wolf/Barnaul with a .223 AK: at around 6-7000 rounds, my accuracy became erratic and group sizes increased dramatically. It jumped from 2 MOA with 75gr match ammo, to over 6 MOA when tested with the same lot ammo. I still haven't replaced that barrel because it's going to cost upwards of $500, plus the cost of a replacement barrel.
Looking at the "steel case" test Andrew Tuohy did for Lucky Gunner, it seems to match up. He was seeing accuracy suddenly fall off with all brands of Russian .223 in a few different barrel types around 6k rounds as well.
Comparing that with an old US Army machine gun barrel life study using 7.62x51, in which both copper and steel jacketed bullets were used in different combinations with cooler burning and hotter burning powders, they found that powders with higher flame temperatures shortened effective barrel life the most consistently. Using the cooler burning ball powder, steel jacketed bullets killed barrels due to exceeding the accuracy spec, while copper jacketed bullets failed the spec due to velocity loss, suggesting they were still acceptably accurate.
TLDR: I don't use Russian made .223 in anything with an expensive, rare, or hard to replace barrel. I believe it reduces accurate barrel life to anywhere from half to only one fifth of what it could have been if US spec ball ammo was used. I'm confident that US made 55gr and 62gr ammo should have the desired features. Other ammo, I just don't know.
