Despite all this excruciating nit picking, if someone gave me an elk hunt and said I had to use a 300 Weatherby I'd be on the plane pronto.
I've shot them with a 300 Weatherby and 300 Winchester mag and I'll be damned if I could tell the difference.You can lump the 300 Weatherby, 300 Win, 338, 340 Weatherby,8 Rem mag all in a pile as far as I'm concerned. Seen elk killed with all of them.
Trying to distinguish the effects on game from such closely matched cartridges is a waste of time.