Thanks! I need to research what the process is for a lathe.I don't have access to a lathe so I use a little cutter from Brownells, you just choose the appropriate bore pilot and just carefully start removing the metal, the pilot keeps everything concentric. You can use a 45deg or I have a less radical 11degree, works well for revolver cylinder chamfers as well. I did that barrel in just a couple of minutes, it doesn't take much.
BROWNELLS 45 DEGREE MUZZLE/CYLINDER CHAMFERING CUTTER & STEEL PILOT | Brownells
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