http://www.dailymail.co.uk/new...-warship-cannon.html
Yes that's what big bore muzzle blast looks like ! At 20 rounds per minute too !

Nice!
I see some yaw on that 5-inch caliber "bullet" so close to the muzzle. Wonder what twist rate they use on that barrel?
Do they still use blackpowder in those shells?
If it can fire 20 rounds per minute, surely it is in a brass "cartridge case" instead of bags of powder shoved in behind the projectile ... empties would make nice lamps or flower vases.