I edited my original post to better state my question. But to expand a little, my rifle has an 11.5 inch barrel and a permanent 5.5 inch flash hider. I bought the rifle before I had a clue as to what I was doing. Now, I use the gun for three-gun competitions and think it's a waste to have 5.5 inches of flash hider when I could have 5.5 more inches of barrel. So I'm thinking of swapping out a new 16" barrel. But if the 11.5 inch barrel has a negligible effect on bullet trajectory / accuracy / whatever, then I may use the money elsewhere.