I designed this concentricity gauge which as best I can tell is fairly unique as it supports measuring both OD and ID of the neck. Like the 21st Century, it uses a test indicator gauge which is more accurate than plunger style dial indicator seen on most designs.
Precision is maintained via inexpensive, yet precision ground ball bearings rather than relying on other options which may induce additional measured runout. And yes, it bolts down to an Inline Precision mount.
If you're interested in building your own, the STL files for printing, BOM, and instructions are available for free: https://www.printables.com/model/1136890-precision-reloading-concentricity-runout-gauge
Precision is maintained via inexpensive, yet precision ground ball bearings rather than relying on other options which may induce additional measured runout. And yes, it bolts down to an Inline Precision mount.
If you're interested in building your own, the STL files for printing, BOM, and instructions are available for free: https://www.printables.com/model/1136890-precision-reloading-concentricity-runout-gauge