Many .458's have no trouble making factory and over 2,200fps with today's powders.

My .458 Alaskan Model 70 easily did it in a 2.1" case with a bit more capacity than the Win Mag., but using Win. Mag. data in 24" bl.

The .30/.338, used for a time as an intermediate US Mil. sniper round, easily duplicates the .300 Win. Mag. factory loads, as will the .300 H&H Mag.