A few years ago, I bought a .458. Normally not my kind of thing, but the price was right and I had a set of dies lying around. Built on a 17 Enfield action, it's big, it's heavy and it's rather ungainly. Whoever built it as a young man in the 50s had dreams of going to Africa which never panned out and it was relegated to being a range toy (whihc it is quite good for). They set it up with a 2x Leupold long eye reliefe scope which leaves much to be desired, and it has the base to a Lyman receiver sight attached, I need to pursue getting that figured out, I'd rather have a good peep sight.
ANyway, I played around with it quite a bit from the bench. The old man had a bunch of the Lyman 500 grain RN bullets and I had quite a few various things I had cast up for .45-70. Among other stuff I got from Dad was quite a bit of AA8700 from when they were selling it dirt cheap in the '80s and I recalled where Dad told me he used it in .45-70, sometimes with a kicker charge and got good accuracy, but unburnt powder and soot. I figured, "why not?" and tried it. Magnum primers, heavy bullets and a good roll crimp and it's a hoot to shoot, recoil ain't bad, accuracy is pretty good at 100 yards, lots and lots of smoke with that inefficient powder and bullet lube, you'd think I was shooting black powder. Pretty fun times.
That rifle will never see the hunting fields, at least not with me, just too darn heavy and ungainly, I think it weighs 13 pounds. But it is fun. Has me looking around for a .458 now in some configuration that would be more useful to load down to sane .45-70 ballistics and actually use.