According to the
http://www.constellation.org" target="_blank">
USS Constellation website, the ship was built in 1854 as the last all sail propelled vessel of the US Navy. Her original armament was as follows:
Main Battery (gun deck): Sixteen 8-inch "shell guns" capable of firing the innovative "Paixhains" design exploding shell, and four 32-pound "long guns" firing solid shot.
Secondary battery: Two 10-inch pivot guns on the spar deck, one forward and one aft.
Boat howitzer: One 12-pounder "boat howitzer".
The barrels are clearly more modern than the Royal Navy pattern used on the
USS Constitution but I wonder if they are real (or models/replicas of a real pattern) or someone's opinion of what cannon should look like. They sure don't look like 8" bores.