I posted about a problematic M70 Yugo AK a couple weeks ago in another section. Aside from some feeding issues, I am encountering stuck cases. They requir a few hard raps with a wood block to extract. I've tried 4 different loads, one being brass. Brass ammo had no issues, so it's not a "brass after steel" problem. The bore has visible circular milling marks and the spend cases have unusual and uneven marks. I would like to polish the bore up. What do you suggest?
As I am not a gunsmith, and not much of a AK guru, I don't intend to remove the barrel.