140 grain Nosler Accubond with the 52.5 grains of H4350 - I chronoed at 2850. I tried Barnes and could get the patterns very tight and they weren't coming across the chrono as fast either. I tried several different brands of bullet, a few different powders, but when I saw how tight the current combination is, I quit. I can get them going faster, but my groups start to fall apart.