Oh dear
I suppose this will be more difficult then I thought.
I don't really plan on using this for HD but I certinally don't laugh at the idea of a 100gr slug moving at 1800fps. or even 4 balls of 00.
I think this would make a really fun plinking and small/medium game with the feeling of an HD gun but with a longer barrel practical for game and basically 0 recoil. I just love the short LOP feel of a collapsable stock and pistol grip.