If I can, I cut at 90 degrees to the bore. I like to use a TPG-320 in case if its chrome lined.
Other than that Go to brownells and get a 11 degree which is really a 79 degree Facing cutter and pilot.
When using the Facing cutter I like to place a lock ring around the cutter. This will stop any tool chatter at the end point.
Failure is part of success!
This year will go down in history. For the first time, a civilized nation has full gun registration. Our streets will be safer, our police more efficient, and the world will follow our lead into the future!" -Adolf Hitler,1935"