On a similar, but less destructive note, the Russians developed several cartridge 'guns' that could be fired under water with impunity. I do not remember what they were called, but I think they were developed for use by their 'frogmen'. The intended ranges were short. One thing about water, it does not lend itself to compression, so I'm not surprised to find that it damaged the shotgun you spoke of as soon as the pressures were suffucient to do so. Its just a dif type of obstruction. Perhaps someone here will post a link to the Russian underwater cartridge 'guns'. There are also 'shark sticks' as I think they are called, essentially a 12ga. chamber rather than a bbl that that is mounted on the end of a pole and that fires when pressed against something, like a shark. I think they work below the waterline as well as above, but I have only read of them and never actually used one nor seen one used. I'm not a TV kinda person, so I did not see the show you ref. but it sounds like something that was discussed sometime ago here or perhaps on another BBS. I kinda view it like ol' 'Fodder Wing', sticking some straw on his arms and leaping from the barn loft .. lucky to survive the misadventure. The line between curiosity and stupidity is sometimes hard to define, but it it most assuredly nonetheless there. I'd define it like this .. curiosity enlightens where stupidity hurts.

As an aside, there was quite the discussion on the old board right here on the origin of terms, 'watertable' being beaten quite flat before it was over ;-)