Years ago I told John Carney I was having trouble with his version of the classic Victor/Vernon routine with five coins and and a champagne glass (which uses an edge grip and at one point requires a 4-coin roll down (or coin star, or whatever you call it). He suggested that I have my old Morgans re-milled by a jeweler with a jeweler's file, which I did. The guy who did it for me was younger and had just started a custom jewelry business, so he was anxious for ways to generate income (so I'm not sure just any jeweler would be willing to do it). The coins don't have that pretty milling that Jamie Schoolcraft would do, the edges were a little bit rough to be honest, but they were really "grippy" and allowed me to master the Carney routine. By the way, if you ever have someone like Schoolcraft re-mill a set of coins for you, he can adjust the "grippiness", so you need to tell him exactly what you are looking for.