As to the 257 Weatherby,
my Accumark was the cat's meow!
However,
I've Been There
Done That
My go to load was a 100 Gr. Nosler Partition over 73 Gr. IMR 7828. Over my Shooting Chrony, velocity was +/- 3,650 FPS.
It flat killed schitt dead as a hammer.
Problem is, I'm a short range meat hunter. I'd say most of my shots are 200 yds. and under with say 80% of those being 125 yds. and under. I find that cartridges with a MV of 2,800 fps do much less meat damage at those ranges.
Consequently I've moved on.
JAPPFT,
GWB