The .458 Alaskan is a 2.1"case, necked to .458. This was first done back in the 40's or 50's by Harold Johnson. The round was called the .450 Alaskan and used .348 Wichester brass which is almost identical to the WSM brass. Since the original .450 Alaskan required a rim to work in the M71 Winchester lever gun and I wanted to chamber it in a M70, I turned the rim off and curt a new extractor groove. This is a 15 second job on a small lathe. The result was what I called a .458 Alaskan. It has a couple gr. more capacity than a .458 WM, works through a normal action and therefore delivers 2,200fps with 500's if you so desire. My favourite loads for BC was a 350gr. X at 2,300fps. This was a light load.
; I assume this 'new' .458 Short magnum is 1/10" shorter than the .458 Alaskan & therefore, something new. Actually, there is rarely anything new - it's pretty much all been done before.
; Good round, though.