Is yours counter bored? I've never checked the throat erotion on mine, to be honest I'm not really sure how
Mine is not counterbored and the from the muzzle end it looks great. I'm really not sure how to check for throat erosion either. I have never used a bore scope, but if you look through from the chamber end the lands are faint at the very start, but look pretty sharp the rest of the way down the barrel. I guess that means its been shot a lot, but I could have been made that way, I don't know.
It still holds what I believe to be a good group with surplus ammo.(3 to 3 1/2 at 100 yards) It shoots the surplus better than some factory ammo. I guess it was just made to shoot the surplus stuff. I'm not sure if the Yugos put a new barrel on it, or if it still has the German one.