Step Drill 5/16″ Pilot 7/32″ (.218)

5/16″ Step Drill with 7/32″ (.218) Pilot to fit Hidden Bolt Rivets 5/16″. The step drill is a standard twist drill which has been ground to a smaller diameter on the end. It enables the user too drill a rivet hole through the handle slab with a counterbored hole for the rivet head in a single operation. Select a drill size that is the same diameter as the rivet head and a pilot that is the same diameter as the center section of the rivet.