Load data from Barnes says 55.0 is max, I'm at 55.5 with great accuracy. At 56.0 accuracy dropped off. Barrel just doesn't shoot Barnes bullets fast I guess...
Harmonics. If you feel like fooling with it add a pressure point in the forearm. Gradually increase pressure and watch the results. Sometimes it helps, sometimes it hurts. I think it's one of the easiest ways to fool with harmonics without hanging a weight on the muzzle.
