Think I know what you want,,,, mount the wheel in a three jaw chuck, gripped in the outside jaws, if your chuck is big enough as the wheel seems to be about 5" diameter, and use a single straight knurling wheel mounted parrallel (spelling?) ie in line with the lathe bed and on centre height, slow speed and lock the saddle, feed in with the topslide.
Hope it helps!!!
Peter
Or even the inside jaws if you can grip the insde of the rim. You really need to give some support to the back of the wheel for the knurl to press against. That seeems an awfully big wheel for a rifle sight.. 130 mm dia!
Edited By Aestus57 on 10/04/2012 16:05:09