My new 300 wsm is finished and a friend who shoots 1000k is working up some loads for me. So for it shoots several bullets in 1/2 inch with more than one powder. I will post the rifle specs and finished loads in a few days. Basically it has a Montana Rifleman short magnum stainless action with a fluted 1/12 Kreiger barrel. I was wondering if anyone has tried H414 or H1000 with this caliber and if so what where the results. Also , would like to know if these powders are sensitive to temperature differences.