I bought a Ruger AR 5.56 with an 18 inch barrel a couple of years ago. It's still new in the box, haven't had time to shoot/set it up. I'm contemplating a vortex strike eagle 1x6 scope for it. Anyone familiar with the performance of this rifle? Could I get 3" groups at 150 yards? If so I think I may want to go with a 1x8. Looking to get an opinion if the 1x8 may be overkill for this rifle. Thanks for the replies.