Another good test would be to shoot them again only instead of having a plastic lid for the bullets to go through first, have several layers of cloth or jacket. It will test if the hp's plug up with a BG's clothing, and how that effects performance, unless the guy is wearing a pail as clothing
I have a NOE 230gr hp mold coming shortly and will be doing my own testing of that bullet plus my alloying abilities.
Is your cast alloy that 97-1.5-1.5 (IIRC) from previous testing?