Where do you think tissue damage comes from? Since you can't measure tissue damage with a chronometer, you got to use what CAUSES tissue damage to measure it.
Well documented studies of energy/tissue damage/bullet types abound.
Helps if you read the articles provided before commenting.
800 ftlbs for deer, 1000 ftlbs for elk
Hunting big game with a muzzle-loaded patched round ball has its limitations, and hunters should know exactly the maximum effective range of the rifle and load hunted with.