Assuming you mean the steel cased Russian stuff, I used Wolf and Brown Bear in 5.56, 9mm, .30carbine and I believe even .45ACP with absolutely no problems. Several years ago at Calverton I tested the Wolf 5.56 (steel cased) for accuracy (given it was only 100 yds.) against Winchester White Box, Remington UMC, Lake City Federal and possibly Brit Radway Green, shooting my AR about 30 to 40 rounds of each. Wolf was more accurate than the Winchester, same as UMC, and slightly less accurate than the Lake City. While Wolf was slightly dirtier (given the days I only shot Wolf since its 50% cheaper) I considered it a bargain. I will also say that the AR had no "burps" with any of it, no FTF and no FTE. My 9mm CZ75 loves the stuff although the M1 carbine occasionally had a failure to feed. I only had about 500 rds of the Wolf and Brown Bear 5.56 left and since I shoot pistols more often at Mitchel Field, I sold it off last year. Now I also have a Mossberg MVP in 5.56 and despite it being a bolt action it feeds better with actual brass than with steel cased, despite it using the same M16 mags that the AR uses.