I set up a 458 WM on an older SF CF magnum action.
It came with a 300 WM magazine and that worked after a bit of fiddling
with the lips. That said I would imagine there are some out there that would not work.
Think I just got lucky.

If you are not shooting at Godzilla and you reload and still want a sledgehammer bullet
you might want to try out the 458 300 gr TTSX bullet designed for the 458 Socom.
A bit less recoil especially if you download. Full tilt the recoil was
snappy and still up there.

The petals might shear off at 458 WM speeds, but that might be a benefit
depending on what you are shooting.

I would strongly suggest getting a Duramax Stock.
Helps tone down the rediculous recoil especially if your rifle is light.

RL7 is pretty much the powder, or at least one of the good ones for pretty much all bullet weights.

I had a 21" bbl

300 ttsx over 68 gr makes a good reduced load chrono at around 2300 FPS
2200-2300 in my rifle was pretty easy to shoot and the recoil was comfortable compared to the full tilt loads below
with even this bullet.

72 gr is as high as I got and that chrono'd at 2475 FPS
Primer and brass was fine with more room to go, but that was overkill so I stopped.
Recoil was very snappy.

Also tested some 600 gr barnes solids. 67 gr got me to 1875 FPS with flattened primers
and you could not shoot it off the bench. Well not more than 2 shots anyway.
Standing was okay though.
It was a handfull.
Recoil was not as snappy as the full tilt 300 grainer, but it was still rediculous and harsh.
Hunting standing I dont think you would notice it much.
Seems like I figured it was 60# or something like that.
35-40# is okay for me with a good stock, but over that gets very uncomfortable on a bench.

Funny go shoot some full tilt 500-600 gr loads then pick up a 30-06 and it feels like a pellet gun - LOL.

Probably also need some Burris extreme rings or something like that.

My barrel had an extremely long freebore and dumped the pressure and FPS a lot.
If you dont have a barrel with a huge freebore the loads above are probably
over pressured.

My gun weighed about 9-10#.