I just picked up a Redfield Battlefield 3-9x42. After looking through Vortex (I own 2, they are also excellent for the price), Burris, and many more "budget" (These are as low as anyone should go) scopes I think it takes the prize. It is so close to "as clear as" my Leupold Mark AR 3-9 I'm a little mad I paid more for the Leupold(only a little mind you). It's MOA/MOA and it sure holds up to a .308 bolt gun, which has a little more kick than a AR-10. Check it out, this scope fits and works just as well on a bolt gun as it does on an AR.
As a side note make sure the scope is focused, as most aren't on the showroom floor. I almost walked away after looking through a second Battlefield, but remembered a review I read stating how fuzzy the crosshairs were. I checked and then changed the focus on the eyepiece and it was super clear and sharp. It fits my .308 perfect. I'm actually considering one for my Mini-14, but the Mini might go to my niece for a graduation present. At the moment she is all about Iron sights though.