I recently purchased a Howell cartridge conversion for my Uberti 1858 Remington.
cylinder throats are currently .452
The barrel is .454 (grooves)
Bullets are soft lead .454 sized, used in non resized brass.
Black powder only
Planning to ream the throats at .455 with using a coaxial indicator to find center on the mill.
Thoughts? Is 0.001 good enough for clearance?