.52 caliber. 24" barrel. NSN. Browned and color casehardened finish, brass furniture, walnut stock with two screw retained flat brass barrel bands. Single shot percussion mule ear lock breechloading carbine with unaltered round hole loading aperture, lightly rifled bore, sighting groove in breech lever and fixed front sight blade on upper barrel band. Standard Ames and Jenks markings on lock, standard markings on breech, which is dated 1845. Retains the original, unaltered round hole loading aperture, but strangely the bore is lightly rifled. The original configuration as delivered was a round hole and smoothbore, with most guns later being altered to an oval loading hole with a deeply rifled bores. Round hole examples are very scarce, but the presence of light rifling suggests this gun may have been part of some sort of experimental trials regarding the best way to upgrade the carbines. A very scarce Mexican War to American Civil War era US naval carbine. {ANTIQUE}