The Sinclair Chamber Length Gauge helps handloaders determine the true chamber length from the bolt face to the chamber's neck end, revealing excess case length over published trim lengths.
It is made of 12L14 soft steel to avoid chamber damage and comes with step-by-step instructions for repeated use.
Not suitable for thin-necked cases like 22 Hornet, 218 Bee, or the 30-30 Winchester, and should not be used in handguns, semi-automatic, lever action, or pump action rifles.