The case easily achieved 2,200fps with 500gr. Hornady RN's from the 24" bl.

I didn't like the recoil for my use, so set the barrel back almost 2" and re-chambered it for the .458 2", which reamer I also have.

The load I liked, uses 51.5gr. H4198 for 2,150fps with the 400gr. Barnes SP. My .458 Alaskan required 60.0gr. Re#7 to get the same speed and of course, kicked more - thus, the re-chamber
- however, the .450 Alaskan in a strong action is nothing to sneeze at.

Even in the Model 71 Winchester that H. Johnson used, the first rifle thus barreled and chambered, it was doing over 2,000fps with 400gr. bullets & deadly on brown bears as a backup rifle.