Lyman - an innovator in the field of reloading and shooting accessories - has introduced their Cartridge Checkers. These gauge blocks allow reloaders to quickly confirm that their ammunition will fit in their chamber. Made from solid blocks of 6061 T6 aircraft grade aluminum, each of the three orange anodized Cartridge Checkers are precisely machined to SAAMI minimum chamber dimensions and accept the most popular rifle and pistol rounds. Simply drop a loaded round into the clearly marked cartridge hole. If it fits flush with the top of the gauge, the round will chamber. Checkers are available in three designs covering most common handgun and rifle calibers. Handgun gauge: 380 Auto, 9mm Luger, 38 Super, 40 S&W, 45 ACP, 38/357, 44 Mag/Spl, and 45 Colt Small Rifle gauge: 204 Ruger, 22 Hornet, 223 Rem, 22-250, 300 AAC Blackout and 7.62x39mm Large Rifle gauge: 243 Win, 270 Win, 30-30 Win, 308 Win, 30-06 and 300 WSM.