The 1" across the flats barrel was only made in 54 caliber for the Hawken, all the other calibers were 15/16" across the flats. The Renegade model only used 1" barrels for all the calibers it came in. The Renegade barrels can be modified to fit your !' channeled Hawken stock. T/C is now owned by S&W, and they no longer make side lock muzzleloaders.