I recently came across a Hawken style rifle built many years ago with a Robbins lock and an unmarked .54 cal l barrel. It has 10 lands and grooves, and the grooves are slightly radiused. Its not like the deep radius grooved rifling so common today, the corners of the grooves are radiused but the bottom of the grooves are still flat. Its 1-48 twist. There are no outside makings on the barrel, does anyone know who would have made this barrel? ...Thanks LK