Quickly find deformed bullets
Since most malfunctions are ammo related, and most of those relate to deformed, bulging or otherwise defective brass - 
dropping the ammo into a gauge is an effective way to reduce the chance of a costly malfunction
 
Simply Check Overall Length
Position the OAL Checker below the Ammo Checker, and all rounds will stand out for you to inspect.
You'll find improperly seated bullets and rounds with different bullets this way, and you'll be one step closer to truly uniform ammo.