Ensure that all ammunition is within specifications before participating in a critical match. A single tool is available to verify four popular calibers used in Cowboy Action shooting - .357 Magnum, .44-40 Cal, .44 Magnum and .45 Long Colt. This tool assists in preventing jams, misfires, feeding issues and other malfunctions caused by ammunition that is out of specification, which could result in the loss of valuable points or the entire match. It is constructed from machined aluminum with check holes that are precision bored using high-quality Clymer reamers. Our case gauge ammo checkers are precision-engineered from solid 6061-T6 aircraft-grade aluminum, ensuring superior durability and performance in demanding environments Our precision-engineered gauges are meticulously crafted to adhere to the SAAMI minimum specifications, ensuring optimal compatibility and performance across a wide range of applications While certain manufacturers employ standard boring bars for chamber checker production, we utilize authentic Clymer reamers, identical to those used in precision barrel chambering processes Anodized matte black finish for enhanced durability The Cowboy case gauge is engineered with a precise height measurement of 1.60 inches, ensuring optimal compatibility and accuracy for your technical requirements The SAAMI specification dictates that the maximum cartridge length for a .357 Magnum is precisely 1.590 inches The maximum specified cartridge length for the .44-40 Winchester, as per SAAMI standards, is precisely 1.592 inches The maximum cartridge length specification for the .44 Magnum, as per SAAMI standards, is precisely 1.61 inches The maximum cartridge length specification for the .45 Colt, as per SAAMI standards, is precisely 1.60 inches