Yay large guns. I didn't fire it, but there is something totally surreal about sitting on the flight deck as close as you can during CIWS zeros. Watching the 'little' cannon as it tracks and then just lights up in destruction. Its a shame we're ditching 'em for the roboturret launchers, CIWS still wins in terms of awesomeness even if it is horribly inefficient. Always gives me a little grin to see the CIWS tracking shit when anchored in port.
Largest cannon I've had the pleasure of actually firing was at a Gettysburg reenactment, I've never actually participated in them but I knew someone who was big into it. Nothing like the concussion from those things.
Edit: Actually shit, I can't believe I forgot about the railgun. I didn't get to fire that one either, but watching it is worth it anyway. 1cm bore research project back when I went to NCSU. Turned several inches of steel into interesting modern art.
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