The Wilson Adjustable Case Gage allows reloaders to measure case length from the base of the cartridge to the shoulder as well as the maximum case length. This process shows the reloader if ammunition is being produced within industry specifications. Notes: This is a two-piece adjustable cylinder-type gauge for checking fired and resized cartridge cases for cone-to-head and overall length Used to compare cartridges avgainst the minimum and maximum SAAMI cartridge dimensions