I have come near the ending of load development in my .300 Win Mag and have narrowed my powders down to IMR 7828ssc and H4831. Both are within 10fps of each other and I am getting an ES of 11 and a SD of 4 with the 7828 load and an ES of 24 with a SD of 9 with the H4831 load. Accuracy goes to the IMR 7828 as well and pressure signs looks very much the same. The only thing holding me back from continuing with the IMR 7828 is that it's not known as an "extreme" or temp stable powder. The H4831 is very consistent across a wide range of temperatures and if I had more of it left I would fine tune my loads by .1 or .2 tenths of a grain to tighten up both accuracy and ES. Where I live it can be 10-35 degrees during deer season and in the 90s like its been this summer, and now is when I do a lot of practice and long range shooting.
I am going to order an 8lb keg of powder and cannot decide for the life of me whether to stick with the IMR 7828 and risk the possibility of temperature instability, or buy 8lbs of H4831 and roll with that. The 7828 is shooting under 1/2 MOA with 5 shots and the H4831 is around .75 MOA. I know if I test 4831 on a better day without as much mirage, the groups will shrink, and tinkering with the charges some will also lower the ES. I am caught in a dilemma and can't make up my mind. Any help or suggestions are appreciated, thanks guys.