Ah, yes, the .416 Taylor carried the mail for Sir Spruce with a 325-gr X-Bullet at 2600 fps, sectional density of 0.268,
very much like a .458-400gr with SD = 0.272.

Little bigger hole with the .458-400gr so maybe we could get by with 2400 to 2600 fps MV in the SAAMI .458 WM and .458 WM+ ?
This will require use of monometals like the X-Bullet.
Maybe someday a .458-400gr brass hexploder ?

400-gr solids at 2600 fps might gain stability from their shortness.
I guess a 400-gr round-nosed solid might stay straight for greater depth of penetration than a 500-grain round-nosed solid,
but that ain't saying much.
Could a higher velocity .458-400gr FN or HYDRO keep up with a heavier and slower .458-caliber FN solid ?
Probably.
As Sir John suggested, adequate for elephant.

Ron aka "Rip" for Riflecrank Internationale Permanente
NRA Life Benefactor and Beneficiary
.458 Winchester Magnum, Magnanimous in Victory
THE WALKING DEAD does so remind me of Democrap voters. Donkeypox.