I used to have a profound theory on bullets striking big game animals once upon a time!

However, as I got more and more into ballistics, shooting more and more animals and testing various bullets, I soon found out that causing big shallow holes on larger animals, was not the ticket to get me on the train. I also got into the velocity bubble, wanting more and more bullet speed but that too sometimes became very disheartning as my bullets became nothing more than frag pieces of jagged metal.
Then I began reading things written by Elmer Keith, Jack O'Conner, Bill Jordan Skeeter Skelton and Fred Huntington. I had conversations with experts such as Joyce Hornday and John Nosler too, mostly about their bullets and do's and don'ts on big game animals etc. I soon got into reloading my own bullets for hunting. It opened up an all new world to me back in those days of yesteryear.
I learned the principles of the Nosler Partition bullet, it was the very best of both worlds for big game. Well, at least that is what I was lead to believe and those bullets worked for the most part but nothing is perfect in this world and I also found out the same it true with even the best of bullets. I did have some of those bullets fail too.
Velocity also was something I had to learn to deal with concerning my hunting bullets on big game animals. You upping that velocity, it is like hopping up Dads engine in the family 49 Ford, what ever you do to that engine for more horsepower, you best beef up the trainsmission and rearend as well, or soon you will have a break down.
Velocity gets upped over 2850fps and the good common deer bullets starts to go to pieces on bone and flesh of animals to be harvested. I soon learned that velocity can be very disheartning to a hunter using bullets, that were not meant to fly that fast. In other words, they won't stay together in particular situations, very large animals, with bigger bones being struck by the bullet for starters.
I soon learned that the big BOOM effect (Bullet fragging inside the animal) on a larger big game animal was not always the best route to follow. I lost my first bull elk with a .270 Winchester and 130 grain bullets years ago because it did just that BOOM and made a large whole (rose wound) never penetrating that all important front shoulder I was told to aim for an a bull elk. The bullet never reached the vitals of the bull!
So in closing I will only say, that as a hunter, I want my bullet to enter causing tissue damange but destroying those vitals and then exit leaving a blood trail for the hunter to follow, if things should come down to having to track the animal. I still like Nosler Partiton bullets for big game animals under 450 pounds in weight but I have come to adore those TBBC bullets, Swift A Frames and Woodleigh Solids, school is still out for me on the TSX Barnes bullets. Cheer's Mate!

Good hunting to you!