4,200 Type I Gwyn & Campbell "Union Carbines" were manufactured circa 1863-1864, also known as "Grapevine Carbines." Gwyn & Campbell carbines were issued to a number of Union cavalry units primarily from the Midwest and West. Manufactured by Edward Gwyn and Abner C. Campbell, the Gwyn & Campbell was the successor to the Cosmopolitan carbine, and manufactured in the same factory out of Hamilton, Ohio. The Type I variation of the Gwyn & Campbell is distinguished by its long serpentine shaped hammer and loading lever. This example has the shorter 600 yard folding ladder rear sight. It also has a blade front sight with pyramidal base, left side sling bar and ring, and standard markings. Matching serial numbers underneath the breech end of the barrel, frame, and breech block. Very faint boxed script inspection cartouche visible on the left of the stock wrist.