Lyman Chamber Checker

Lyman's Cartridge Checker quickly confirms whether your ammunition will fit in your firearm's chamber. Machined from solid blocks of 6061-T6 aircraft-grade aluminum and cut to SAAMI minimum chamber dimensions. Simply drop your loaded round into the checker and if it fits into the gauge, it'll fit your firearm. Each cartridge is clearly engraved on the gauge. One gauge works with a variety of cartridges. Available in three designs to cover most common handgun and rifle cartridges.
Available:

• Handgun (fits .380 auto, 9mm Luger, .38 Super, .40 S&W, .45 ACP, .38/.357, .44 Mag./Special, .45 Colt®)
• Small Rifle (fits .204 Ruger, .22 Hornet, .223 Rem, .22-250, .300 AAC Blackout, 7.62x39mm) (not shown)
• Large Rifle (fits .243 Win, .270 Win, .30-30 WIn, .308 Win, .30-06, .300 WSM) (not shown)
• MSR (fits .223/5.56, 6.5 Grendel, 6.8 Rem SPC, 7.62x39mm, .300 AAC Blackout, .450 Bushmaster, .458 SOCOM, .50 Beowulf)