Product DescriptionHornady Lock-N-Load Rimfire Thickness Gauge .17 - .22, RF17.
Sorting ammo by rim thickness will provide ammo with similar ignition qualities for improved accuracy. This proven technique is used by competitive shooters, target shooters and varmint hunters. The Hornady Rimfire Thickness Gauge attaches to your caliper (any style of 6" caliper) and includes bushings for use with all .17 and .22 caliber rimfire ammo. The gauge is used to determine if any significant variations are present in a "lot" of ammunition. Ammo with less deviation in rim thickness should shoot more accurately. Wear lanyard around your neck and attach to caliper to promote safety.