Lyman's Ammo Checkers check the quality and consistency of both reloaded rounds and purchased ammo. A must for any auto shooter for easy and consistent feed. You can't afford misfeeds, so get the easiest "no-go" gauge available today!Specifications and Features:Lyman's Small Rifle Ammo Checker Cartridge Gauge works for 204 Ruger, 22 Hornet, 223 Remington, 22-250 Remington, 300 AAC Blackout, 7.62x39mm