21st Century Primer Pocket Plugs
H2O weighing is a technique used to sort cases based on volume. By plugging the primer pocket, the case can be set on a precise electronic scale, filled with water and weighed. Subtracting the weight of the case and the plug from this measurement gives us the weight of the water in the case (a direct indicator of volume, no math necessary here) and the sorting process can begin.
Plugs are available for both small and large primers.