I own a Series 189 Mini-30 It has shot nothing but Wolf 7.62x39 for 7 years. When I bought it, I contacted Ruger about using the Wolf ammunition. They had no problem. The Wolf ammo was .311 and Ruger informed me the Mini-30 barrels were nominally of .310-.311 diameter. I've fired almost 6,000 rounds with no problem and very decent accuracy. The Series 189 rifles have very deep rifling and the barrel on mine still appears shiny with sharp, well defined rifling having sharp edges. Actually, the rifling in my rifle appears much as did the rifling in the AKs I owned; very tapered from base to top and deep. I dumped my last AK when I bought the Mini-30; its ergonomics (stock and sights) allowing much quicker and accurate shot placement than the AK.