Just remembered this.
Back in 77 or 78 while guiding moose, goat, bear and wolf hunters in Nothern B.C. two of the hunters had .338's. One was shooting 300gr. Winchester RN's while the other was shooting 250gr. partitions.
My buddy Keith, who absolutely loves his M1917 in 8x68, also is a .338 Mag. Lover. His favourite bullet was always the 275gr. Speer at about 2,500fps. Due to his magazine, he had to seat them quite deeply out of the VERY long ogive, so he had a CH4D cannelure tool and would run another cannelure out on the nose. This turned them into a bullet similar to the H-mantle bullet, in that they expanded beautifully back to that cannelure, then stopped expanding at that cannelure and turned them into super penetrators, better than Nosler Partitions as they ended up with a lot more body mass behind the expanded portion.