Have you tried any H110/296 powder? It does well with max loads and should put you right where you want to be easily. I've seen in the past with it and with shooting up 3 lbs of 300MP is that it will do what 300MP will do with a little less powder charge. Hodgdon's load data shows 21.0 - 22.0 grains for H110 or 296 with Hornady 125 XTP bullets and mag primers.