I think that while I haven't used it, there is a difference between a 44 Mag with full house loads and a 500SW. Nobody has done terminal ballistics study of 700 Grain Underwood factory 500 SW ammo. My view is why the hell not!
Muzzle Energy: 2238 ft. lbs. for 700 Grain Underwood.
Energy: 833 ft/lbs from 7.5” barrel= 44 Mag Garrett hammerhead 325 grain bear loads.
500 SW in chest holster while packing meat is good insurance.
I've tested 700 grain handloads (using Ranger Rick's 700 grain bullet and it looks like Underwood is using one of their molds) and they were an abject failure. Too much of a good thing. In wet pack they wouldn't track straight.
