A milling machine would be the ticket.
But if you don't have one of those, maybe you can use a drill press, so that the "jigs" are all the same depth and to give it some uniformity.
I have never tried it. But would suggest only using a sharp ball bit, and go slow and easy. Drill presses are not made to withstand side pressure, and may wear out bearings if you work it hard. Speed is anybody's guess, but my guess starts with high speed.
Dan