The rifle is chambered in 5.56 so I will be getting the cheaper and more available .223 cal. As for brand names I have read that Black Hills, Hornady, Winchester, and Federal are all really good. I didnt plan on buying different boxes of 20 rounds just to test and see what I like.I was going to get a case of 250 or 500. This is the reason I am asking you guys about ammo types and brands. I want something that is plenty accurate, clean, reliable, and not too expensive (remember this is for casual target shooting at the range only). Also how much of a difference in accuracy for FMJ, HP, SF, etc...? about the steel cased ammo, I also have an SKS and bought 500 rounds of Wolf "military classic" FMJ for real cheap. I guess I should be careful when shooting it right?, mabey do a quick cleaning after every 40-50 rounds. I definately don't want any crap ammo going through my AR which I have about $800 invested into. So I wont be getting Wolf or any other steel cased ammo. Thanks for all the help!!!