What is the best powder for 223 and 308 for hot weather, above 100 degrees? Is Varget the best choice? I live in Phoenix and our summers SUCK. They last for about 6 months of 100+ degrees every day Some days are close to 120. What is the best powder for these temps? Im guessing whatever is close to what the military uses has to be good since they run max pressure loadings in extreme heat areas in the middle east.