Do you think you could make a bushing that I could use the anschutz inserts in . Basically it would have a OD of 20 mm and a ID of 18 mm that would center the insert in the globe sight . I could draw up a set of plans . I would need a thin spacer for the front of it so the jam nut would apply pressure to the insert . A complete set of 10 inserts is $20.00 . Marvin