That's a good point GPS. So far the FMJ's,both round and flat have fed well in my XD45. I thought I read somewhere in one of the manuals that Honady HP's needed to be set just a little deeper in the case than FMJ's. That doesn't sound right to me but I am kinda new at this.
Also,I haven't found load data that's specific to Hornady 230gr HP XTP but I assume that the 4.9gr of Winchester 231 that was recommended for the FMJ round and flat nosed bullets should be okay.
So far I have kept the overall case length in the the 1.140" range. So if I understand what you are saying, if I stay in the overall case length range I should be okay regardles of round, flat, FMJ or HP?