There is a saying about 'carry a big stick' which seems to apply here, methinks! Kudo's to you!
I've never even held a 500 S&W and won't but have shot a 475 Linebaugh with a 400 gr at 1000 fps, and there is something to be said for heavy large diameter bullets moving at a moderate velocity. Recoil is easy to handle yet they hit a bit like a D9 Cat,
The important thing is to keep displacement velocity under 135 max for fastest kills. Your load is quite a bit over that, which I think might be the reason it traveled as far as it did. On the other hand, large hole do not fail to make animals expire quite promptly. What I'm saying here is to the readers who have a .4+ caliber revolver up to .45, you don't need to get a .500 to get this kind of kill. Just read this forum over and you'll get my recommendations.