I inherited an old muzzleloader that belonged to my great grandpa. It is a .40 cal target rifle put together by a Monroe, Wisconsin smith named George Spangler. The barrel is marked "Remington Cast Steel" and is plenty thick but was caked with rust down into the grooves. A shop instructor in a machining class showed me how to make a freshening cutter. I embedded it into a 3/8" dowel rod and shimmed it out with paper strips until bright steel cae out after awhile. It now loads smoothly and is alot more accurate than it was with that rusty old bore. The tops of the lands, I smoothed out with automotive rubbing compound until the patches came out clean. A lot of spare time over a couple of months is what it took but it was worth it.
