Not something you see every day! The barrel would be clamped in, the rod pushed through, a cutter installed and then pulled back through the barrel. Reapeat many times, installing larger cutter each time. then rotate the cutter position and start again.
Set up would do 6 lands or 5 lands.
Twist rate looks to be 1 in 21. So obviously black powder length up to about 24 inches.
400$ plus shipping
Ed
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