Is there any Hornady data for the 155 gr XTP in question? Part of the problem is that you are comparing dissimilar bullets. A Silvertip is not the same as a XTP, nor is the Gold Dot HP. They are somewhat unique (no pun intended) in that neither is a garden variety jacketed bullet. You would be best served if you can locate a Hornady manual. XTP data isn't typically that hard to find because the bullets are quite popular. Failing that, generic 155 jacketed data might be better.
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