Somehow I overlooked the 40.8 load - its a good contender, too if you can get the SD/ES down a tad (maybe look for something between the .6/.8 load?). But my reasons remain the same: Less vertical stringing. As I understand it, while barrels resonate in an oblong fashion, vertical stringing is where nodes and antinodes are most evident. The rifle's center of gravity is generally below the bore axis, so under recoil the bulk of the force is exerted upward, causing a vertical string. In my experience chasing the vertical resonance tends to reduce the horizontal as well. I'm never the person to say what I have learned is law or better than anyone else's experience, but that's what I've come to understand and practice.