I have my doubts.. it's still a pistol cartridge, effectively, just because it says ".500" doesn't mean it's got any oomph to it.. There's a WHOLE lot of rifle cartridges that have significantly more energy than that thing.. The .500 S&W it was modified from has muzzle energy very similar to a .308, which is pretty anemic in this crowd..
Back to the original question, though, I'm surprised nobody here has brought up the .45-70: a wide range of loads readily available, from just a good thumper kinda gun right up to shoulder dislocation, all of which fall inside the SAAMI limits..