IMR 4831 43.00gr
This is a load that I have found that works really well for me out of my 6mm Remington. It will shoot sub MOA. I took a Whitetail at 250yd with this load last year. My guess is that the hornady a-max will shoot just as good if not better than the speer bullet. IMHO,IMR 4831 is the best powder for the heavy bullets in 6mm. Good luck!