The Burnside was one of the most widely used Union carbines of the Civil war. This 54 caliber, percussion breech-loading carbine fired a unique cone shaped cartridge. This 5th model was made in 1864. It features the redesigned breech block with a hinged center section that facilitates loading. The difference between the 4th model and 5th model (Model 1864) is that the 4th model does not have a centrally located breech block guide screw on the left side of the frame which this gun has. This carbine's 21"" round barrel has a fine bore with strong, mostly bright rifling. All the metal has a smooth brown or gray-brown patina. The breech block serial number, 1305, and the frame number match. The standard Burnside markings are present. The sling bar and ring are present. The buttstock is good with no cracks but with heavy wear at the comb and sides. The two cartouches are easily visible. The forearm is good with moderate usage wear but no cracks or chips. The action functions correctly. This is a very good representative 5th model Burnside saddle ring carbine that obviously saw action.