Re: 375 cal 350 gr?
A couple of things to keep in mind. The standard twist of a .375 H&H is not quick enough for that long 350 gr SMK, so you may see some instability in an H&H chambered gun.
Another is that there is a theory among some long range hunters that it is best to try for a high shoulder hit, as that damages the spine and drops the animal on the spot. For that hit, it does not matter much if the bullet expands or not.