Bullets that hold together under high impact velocities, like the MRX in your list, tend to defy that trend, IME. Interesting that the .308" 180gr MRX penetrated right up there with the heavy, .458" bullets that you tested.
I think that is because they have less frontal area than bullets that expand into a circle (more or less).
Have to admit I'm very happy with MRX and TTSX. Plan to use a 180g LRX this year in my .300WM. Have yet to catch an X in an animal.
