None of those links worked for me, but it doesn't matter. I recall watching both the owner Kamikaze and the heavy dude both shot the handgun - original videos, I guess.

I also cringed at the way that fellow held the gun and almost wore it in the face as it as it flew back over his right shoulder - then clacked on the concrete floor - sounded like it.

Knew it was a .600 Nitro & seem to remember the lead bullet was supposed to be doing about 1,600fps (IIRC)

Hell of a load for a handgun - no thanks.

I have shot a .500 S&W with factory ammo. The gun had a vented barrel - think 5 or 5 1/2" long bl. It had less recoil than my 4" with the short, fat round butt grips - 300gr. Truncated Cone commercial lead and 22gr. W296.

The .44 stung like a wasp sting in the palm every shot - made me say OUCH!

That big .500 was "almost" pleasant, in comparison - almost. It was still hard on the arthritis in the wrist, but - like said, not as bad as the much lighter .44.

Weight and ergonomics makes SUCH a big difference.

NO way would I fire either of those guns, BigDogs or Kamikaze's. Good on them, though!