Chamber Depth Gauge
  • A cylindrical plug of hardened steel, precisely machined in relation to the standard dimensional specifications of a given cartridge, engraved with circumferential lines demarking the different typical lengths of cartridges available for that bore. By inserting the appropriate bore's plug-gauge into the chamber, one can read off the line indicating the nominal maximum length of the cartridge which should safely be able to be shot from that gun (provided, of course, the gun be in sound condition).