I do that with ANY gun that someone is shooting for the first time...I think I did that when I first fired my .44 magnum - one round loaded. These days I can do one-handed.
As for the 500...a friend has the 460 he loads to the SAAMI maximum. It kicks more than the off-the-shelf .500 S&W loads...I fired it once and will pass on firing it again. I didn't drop it or anything, but that flipping HURT. And the shockwave that hit my face...
I have a 500 with the 4" barrel. A neighbor of mine who owns a gun store gave me an open box of .500 ammo, hot stuff from Corbon, want to say it was 400grain but I could be wrong.
Yeah I found out why there were only two rounds missing from the box, holy shit. I was expecting the pain in my hand and wrist, but the feeling I had
in my teeth was a real eye opener. Some report/shockwave! Probably won't be doing that again.