Looks like the ammo is 1.25 plus...that's 6.25 per cylinder full(five rounder, right?) That'll add up pretty quick if you can handle torching off more than 1 or 2 rounds per outing.

Had a friend who bought a Mountain Gun, as we used to call them. A S&W in 44 mag with a 3 to 4 inch barrel. A bitcching bellering beast of a pop gun. We nicknamed it the hand held nuclear device. I shot it ten times. He shot it ten times and said I hope you enjoyed that, I'm selling it. I said that was probably a good idea. It was painful to shoot.

I can't imagine what that thing you have is going to feel like.