How much does that single at Century Arms weigh? I remember reading a piece on shoothing that monster. I seem to recall a 4" case and conical projectile. Dangerous Dave at Old Western Scrounger imported a bunch of the ammunition for that project and was selling them as curios. Anyway, the author was describing a bright "flash" everytime he fired it. He initially thought it was muzzle flash, but discovered it was actually his retna separating from the back of his eye under recoil...

I can handle recoil, but load it sensibly with roundballs (OR add wheels and a string) and I'll fire it.