Gee, thanks for your condescending and non-illuminating post.
All I've done is shoot various bullets into a lot of different testing media, some of which was capable of retaining the wound channel, and compared not only the channel but the depth of penetration with the diameter of the mushroom and the retained weight.
Often I've fired the same weight of bullet (or nearly so) at the same velocity, from the same rifle, so everything was as close to the same as possible--and many bullets that retained less weight penetrated at deeply, or even deeper, than bullets that retained more weight.
No doubt this could have been figured out with formulas, but one thing I've discovered about writing about firearms is most readers need to SEE something before they can grasp it. Which is why I've taken the time not only to shoot a bunch of test-media over the years, but have gone on a bunch of cull hunts to see how well test media results correlate to field use.
Thanks very much for suggesting I could have just as well stayed home and not wasted a bunch of bullets in actual testing, when fiddling with formulas could have saved me all that time, money and effort.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.” John Steinbeck
