Rastoff
US Veteran
As has been stated previously, it depends on the level of accuracy you're going for.What will the 1-8" do that the 1-9 will not do. I do not have an AR but am thinking about the Sport. I want to shoot 55gr rounds mostly, but if it stabilizes the heavier rounds as well as the 55's then what's the big deal?
If you want to put bullet after bullet through the same hole, you'll need to match the load and bullet mass to the rifling and length of your rifle. Of course if that's true, the AR is probably not the right gun either. However, if you're like most of us and 2MOA (2" at 100 yards) groups are good enough, the 1:8 will serve you just as well as the 1:9 twist. The gun will shoot better than that, but when you add the human factor, groups open up a little.