The U.S.S. Shark was lost in the mouth of the Columbia River in 1846.  She carried 18 and 9 pounder carronades for armament, and to date 3 have been recovered.  One has been on display at Cannon Beach in Oregon, and the other 2, recovered at Arch Cape Beach in 2008 are undergoing conservation at Texas A&M University.  One of these 2 is almost done, and proves to be a British Navy gun,  possibly taken as a prize during the War of 1812. The other gun is still not identified but may be a locally made U.S. gun.  This update from Oregon Live.

Picture of British Carronade

Picture of original Cannon Beach Carronade