I guess i will shoot both to see which my gun prefers. But why are there two different bullet diameters for the 44. I see speer uses .429 and hornady uses .430 the hornadys work fine for me but i will try speer.

There is no real reason that I know of. I think Sierra uses a .4295 diameter bullet. It really doesn't matter, I have shot them all and really do not see where one is better than the other with jacketed bullets, but with lead, then that's a whole other story.