Dave,
You tend to try to do direct comparisons between bullets that can't be directly compared because they're not the same, in either construction or caliber.
Identical weights don't compare directly, even at identical velocities, even in the same caliber.
Identical, or near identical weights, between two different calibers won't compare directly, even at identical velocities.
Bullet construction (even hollowpoints differ greatly), bullet shape (flatnose, roundnose, jacketed, lead), and bullet width (caliber) all produce different results in terminal effects.
Many can be close, but asking if Load A in one caliber will perform like Load B in a totally different caliber is very difficult to answer accurately. Too many variables.
Denis