This is a 16"/50 caliber Mark 7 gun barrel that was removed from the battleship USS Missouri (BB-63) during her 1949 overhaul.
When seen installed in its turret aboard ship, its size can't be appreciated. There's nothing to give it scale. It's only when observed in isolation that one understands how truly ginormous it is. The damn thing is 67 feet long and weighs 120 tons (240,000 pounds) with the ability to shoot a 2,700 pound projectile up to 24 miles. It's hard to believe three were mounted in single turrets.
Enjoy. I shot these in SF during the America's cup.
This should give you an idea of how high they fly.
168 years of America's cup in one frame. The replica of the Schooner America with Luna Rosa Prada
USS Iowa, the last battleship to venture out on the open ocean. I shot these while she was going restoration in Richmond Ca in 2012 before being towed to San Pedro where she is now.
I have a better version of this shot, but I can't find it.