Ive shot all types of ammo, all kinds of wolf, bear, federal, winchester, m67..just all kind fmj, sp, hp. not 1 malfunction. I've got tapco mags, a chinese mag...I believe 2 romanian, or bulgarian metal mags and the 40rd burgraian bullet mag.... ive shot alot at 100 and 300 yards... when i was using my centerpoint scope i would get the best groups with bear ammo mostly around 3 inch groups at 100... about 6 inch groups without the scope. ive shot a 3 inch group at 300 but that was luck...it shoots the worse with american ammo. the finish aint great but I didn't buy it because it was pretty I got it because it works..