I agree with all replies. It takes some skill to properly "benchrest" a rifle, repeatability, as said, is the key. I think there are more .5" rifles out there than .5 shooters, but no problem! You have a hunting rifle, and it sounds like a very good one at that! I can remember when 1" from a rifle was considered "varmint" accuracy! Guess what? It still IS, ha. I know guys who hunt from deer stands, and they like a big scope to see horns & such, finesse the shot. But, a Leupold Ultralight in 2x7 or 3x9 is very small, but plenty of power. I personally like 2x7 and smaller, my Leupold 1.5x5 is a favorite, and plenty of power.
I suggest you think about dedicating this rifle to hunting, and later, pick up a heavy barrel model ( Howa's are great actions, btw) 308/big scope, to "scratch that itch" for .5" and less! Good luck to you, 308 is a great round!