Based on the book of Burnside carbines, the addition of the screw in the frame was brought about in 1863 so this carbine dates from 1864-65 based on that and the under 20,000 serial number and Model 1864 on top of receiver. This was not a closet queen or home guard gun as evidenced by the use. The 21" barrel is basically a smooth blue brown. Receiver is basically grey. Excellent stock with no cracks and sharp cartouche but several war bruises. Sharp as new rifling with some frosting. Action locks up like new gun so even in battle, this carbine was well taken care of. A very popular Civil War carbine and one that saw use but not abuse.