For .357 I went for an 8 pounder of IMR4227 a few years ago and still have a bunch left. Great for mixed power ranges. The lower the boom-factor the more unburnt grains you'll get. This one is for sure a max load powder. If you want a fantastic hot powder for .357 I'd also recommend TITEGROUP. Be cautious of your measure because its a fast burner and easy to double charge and you DO NOT want to deal with a double bang from this one! The good thing about Titegroup is it burns clean and a little bit goes a loooong way!