The Hornady Lock-N-Load 300 WSM Modified Case is a precision reloading tool designed specifically for use with Lock-N-Load Precision gauges. Featuring a specially threaded case-head and perfectly round neck opening this modified case ensures precise chamber alignment and accurate measurements for your firearm.Hornady Lock-N-Load 300 WSM Modified CaseFine thread attachment for perfect gauge alignment.002" oversized neck for effortless bullet insertionThreaded case-head design for secure gauge connectionPerfectly round neck ensures concentric bullet placementCompatible with Lock-N-Load Precision measurement gaugesEssential for precision reloaders seeking accurate chamber measurements and optimal cartridge overall length (COAL) determination for 300 Winchester Short Magnum firearms.