Tim, my calipers are broken... (don’t buy frankford arsenal).

My brother is converting a tricomp to a 5 inch version for me.
He has a machine shop but is 600+ miles away from me. We know he will need to ream the inner wall of the “comp” area to allow for the barrel to float within the device and not touch the comp walls.
He is ask for the diameter of my muzzle and I have no accurate way to measure it.

Any help on the numbers would be appreciated.

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