When I attended Paul Capellos "American Airgunner" shoot last year Lee, aka: Shootist, brought along his dragonslayer which I believe was 50 caliber. This is the only big bore air gun I've ever been near when it was shot so I have no reference to other big bores but I can tell you that the rifle was LOUD !! It sounded like my 12 gauge deer hunting slug gun when it went off. Oh yeah,,,, I forgot,,,,, it was way COOL !!
If NY ever allows air guns to be used for big game hunting I'd run out and buy one in a heart beat !!

Jeff