The 30-30 Winchester Modified Case is specially engineered to work with Lock-N-Load Precision gauges for accurate cartridge overall length measurement and precision reloading.30-30 Winchester Modified Case (SKU: A3030)Special fine thread attachment for Lock-N-Load Precision gaugesPerfectly square alignment ensures precise chamber positioningRounded neck opening allows effortless bullet insertionConcentric design for maximum measurement accuracyEssential for precision reloaders seeking consistent cartridge overall length measurements. Note: Dial Caliper and OAL Gauge sold separately.