Any media test is only a rough guide to what might happen when a bullet hits something. Dry newspaper is harder on bullets than wet newspaper, or almost any sort of gelatin, wax, etc., but it is not bone. It is also not bone held together by tough tendons, like the big shoulder joint of an elk or Cape buffalo.
One interesting rule of biology is that bone mass increases at twice the rate of animal weight. Thus a 500-pound elk has bones that are not just twice as heavy as those of a 250-pound deer, but 4 times as heavy. Elephants have incredibly heavy leg bones, and they are solid bone, too, not bone surrounding some sort of core, like those in lighter animals. So a bullet's ability to break bone (and keep penetrating in the same direction) gets much tougher an animal size gets larger.
On the other hand, it does not take much bullet to penetrate the shoulder blade of even some pretty big animals, and especially not the rib cage. So the big penetration advantage of really heavy bullets is lost there. A pretty light bullet (say a 120-grain from a .257 Roberts) will typically penetrate all the way through a typical elk's chest on a broadside shot. The bullet may not pop out the other side--and elk's hide is tough and stretchy--but it will get through the vitals.
So the answer is--it depends.
JB
