My Father-in-law gave me about 1000 primed 357 Mag cases to reload for myself and him(lucky me!). I have never loaded for handgun b4, but I load for rifle and shotgun all the time. I picked up some 158 gr Speer Uni Cores and some 125 gr Gold Dots. My question is what is the best power to use? I am more concerned with low flash and clean burning rather than blazing speeds. I have some Unique I could use but have always heard it is dirty.