I've been doing my research on different AR platformed hunting rifles. I am custom to a 7mm Rem mag, 270 Win, and even have a 7mm-08. So basically just wondering if anyone would recommend a caliber with enough knock down power to take down big game (deer, elk, eventually antelope) and flat shooting enough to reach out to 5-600yrds without sacrificing knock down power. Am I expecting too much in the AR line of hunting rifles? Rock River Arms and even La Rue have appealed to me most, but before I spend 2-4k on one I just would like some other advice/opinions. Are there cheaper accurate large caliber ARs out there that I should look at?