Any 300 grain bullet ever made, coming out of a 375 is a deer killer.
I have taken deer with the Hornady 270 grain and the Speer Grand Slam 285 grain. I agree with 378Canuck, that about any 300 grain or whatever out of a 375 will kill a deer cleanly
I got banned on another web site for a debate that happened on this site. That's a first