For what it's worth I used a 300 gr. Partition at 2,500 fps on deer. It was the one and only time I experienced a bullet "failure".
The Partition didn't expand. ;)
The deer went down so fast I honestly though I'd missed at first.
the 300gr partition is way too tough and slow for deer out of a H&H! that being said a .375" hole in a deer's heart/lungs is more then enough to bring it down.
if I ever felt like using my 375 H&H to take a deer id use a Speer 235gr hot-cor. these "little" bullets have a pretty good track record for putting deer down fast.
I love those Hot-cor...they are soft and gets the job done quick!