Both the 200gr. Sierra and 220grn Hornady should expand beautifully at 2,000fps to 2,200fps, which the .375/.303 produces.
Ken Waters chambered up a #1Ruger in this ctg. many years ago.
I've used the 220gr. Hornady on 2 moose, big cow and long yearing bull. Beautiful performance on both. Picture perfect expansion on both with only ribs and lungs hit. To the off side& under the hide penetration. Initial vel. was 1,940fps.