300 AAC Blackout Chamber / Case Length Gauge by RCBS carries the RCBS 300 AAC Blackout Chamber / Case Length Gauge. The 300 AAC Blackout Chamber / Case Length Gauge does double duty. Drop the hand loaded round in to check both chambering as well as cartridge length. The 300 AAC Blackout Chamber / Case Length Gauge is made of steel and comes with a Limited lifetime warranty.
