The bbl is 20-1/2" and has a good bore. Caliber is 45 or possibly one of the 433 calibers. Somebody put some sort of protective coating on the metal, which has a rusty orange appearance. Most of this can be cleaned off. Otherwise the metal has a nice grey-brownish patina. Bbl has "E.N." stamped on the top. Wood on this gun is also quite nice. This is a solid little Rolling Block carbine.