roger that. Although I prefer my M1A, when it comes to distances of 500 to 800 yards (which is as far as I can shoot accurately) my AR-10 outshoots the M1A. At least with me behind the trigger it does.
Upgrading to 6.8SPC would only require purchasing new uppers. It would seem like a no-brainer, but 7.62x51 is already in the supply chain I guess.