I have worked up some .500 S&W Magnum loads with some .500 Specials. Use at your own risk.

https://www.midwayusa.com/product/1010200848?pid=266944
https://www.midsouthshooterssupply.c.../006-90991.jpg

http://www.sagesoutdoors.com/500-s-w...tor-gas-checks
the best hunting load I found so far in my 500 mag revolver is the lee hard cast gas check bullet listed as weighting 440 grains,
but after lube and gas check are added they weight about 478 grains cast from 95% WW alloy and 5% pure tin.
is 22 grains of BLUE DOT POWDER, I have not chrono graphed them , but they are very consistent and accurate in my 7.5" revolver
and Ive yet to recover a projectile Ive shot hogs with.(even out at 60 plus yards)

I have a 7.5 inch Magnum Research Revolver and a Bighorn Armory Model 98 carbine both chambered in .500 S&W magnum. The differances in FPS were averages between the pistol and rifle. Also, I just listed the MFG requirements on primers. I used LRP in all loads and powders even where the MFG said to use LRPM. Then I switched to LRPM in all loads in all powders. It did make a considerable differance in FPS. Rather than a large spread sheet with differances I averaged the FPS across the board. Also the the twist rate of the rifle is 1-24 and the pistol is 1-10. I also averaged the differances in FPS between the two. The recoil is managable even with 375 grain HCFNGC rounds. I did shoot a 500 grain buffalo bore round that will wake you up. The special rounds are about the same as a 44 mag in recoil. I can only use longshot and tigegroup in the specials. The other powders at minimum load over fill the cartridges.

https://www.midsouthshooterssupply.c...ld-c501-350-rf
https://garage.grumpysperformance.co...a0c6b95ee3dc55
some of you may be un-aware that lee has produced a lighter weight 350 grain mold for the 500 mag revolvers
these lighter weight projectiles noticeably reduce recoil, I found the same 22 grains of blue dot powder used under that 350 grain bullet,makes a more pleasant target load, yes you can easily increase the velocity further but why?
its already hitting harder than most 44 mag loads can.
yes both LEE hard cast gas check bullets can be pushed to higher velocity, but at some point you really want to ask, whats required to do the intended purpose? if either bullet drops game like thors hammer whats gained by stressing the handgun to higher pressures?