Pretty awesome indeed considering I don’t see anything like it being sold to consumers nowadays, of course technology can improve on having to re-pump it or to use an outside pressure tank. We have all seen high performane .177 and .22 airguns, but nothing like a 230gr. .452 lead bullet or a comparable black powder conical or such.
Would make for an interesting build, especially on a TV reality series. And not a potato gun, something that duplicates the velocity of a rifle fired 45auto.
Check out Quackenbush Air Guns.
.495 round ball @ 850 fps from a modern air rifle.
My brother worked with a group of Korean men for a ~year, many of them, possibly all of them, had big freaking air guns to hunt/target shoot in Upstate New York.
Apparently they do still make hand pumps for these Korean air guns, lots of crude jokes based on it...