So, over the years I have accumulated too wide of a variety of powders for my 300 WM. I have a pound and a half of about 4 or 5 different powders. RL 17&22&26, H4350, MR4000, then I have about 4# of MagPro, and I picked up 8# of 4955. The IMR4955 is every bit as temperature stable as they...