3/8" gun drill with extension for ramrods or through bolt holes.


Another view


Flat counterbore with swivel pilot for bolt head & washer, big enough for the socket wrench



There are instructions and pics on my web site showing how to drill a magazine tube hole for a lever action forend essentially the same way.

Last edited by SDH-MT; 04/29/16 12:38 AM. Reason: edit