contender
Ruger Guru
Here is a ammo concentricity guage for sale. It came from Jim Carmichael, and doesn't have a name on it. I'm thinking he told me it was a Sinclair tool. I can not be sure. In any event, I have more than one of these things, and do not need it. It has a Teclock dial indicator that goes to .0001. I'll take $55 shipped for it.