That is gun drill, designed for deep straight holes, sold by TOW for drilling ram rod holes. The premise is the same but even more careful measurement is required. Additionally a simple jig can be made to keep the hand drill in line. The drill is about .405" in diameter. The jig is simply a hardwood block with a corresponding U shaped notch milled in to it. The block is then clamped to your stock blank giving you the line you desire. I saw pictures of the set up in one of the better books on building muzzle loaders. If I can remember I'll see if I can dig it up.
Steve

Firearms imports, consignments


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