Bill: here's my set up (at the Vegas show this year), and it has given me quite reproducible results. 2 bungee cords hold the barrel securely on the box (in which I keep everything for trasport). It is weighted with 25# of shot.
My right arm does get tired carefully holding the gauge so it stays parallel to the bore without touching the barrel wall. It's easy to rotate the barrel without withdrawing the gauge.
I DO need an assistant to record the wall thickness numbers as I call out the location.



Bill Henry also made me a barrel thickness standard which is .038". I secure it to the table with a C clamp and "re-zero" the gauge frequently.


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