I am like many others, struggling to find certain powders. I apologize in advance if this has been discussed before. Why did powder manufacturer's use the same designations, ie AA4350, IMR4350, and H4350? Can you use the same load data safely between them? I am not expecting the same results with velocity or accuracy, but dang, it seems like if something becomes available I've gotta buy at least three pounds of each to make sure I can do any kind of testing! You can't buy one pound today and expect one stinking pound to be available a month from now!