Redding Instant Indicator Features The Redding Instant Indicator works as a headspace and bullet comparator in one fixture so a single setup on the bench answers both of the questions that matter most when working up a load for a bolt gun. Measuring headspace tells the loader how much the shoulder moved during sizing which is the difference between brass that chambers easily and lasts and brass that is being overworked and stretched toward case head separation. Comparing seated bullets against the same reference lets the loader track seating depth relative to the ogive rather than the bullet tip the only meaningful way to judge how a cartridge relates to the rifling. For handloaders building match or varmint ammunition in .223 Rem that repeatable reference is what makes small changes in a load traceable instead of accidental. This is the version supplied without a dial indicator so the package covers the base tool along with the caliber specific insert and stem while the reloader provides an indicator of their own. Any compatible indicator with the standard .375 inch stem diameter mounts up which makes this the economical choice for a bench that already has a dial indicator on hand from other gauging work. Because the tooling is cut for .223 Rem specifically readings reflect that cartridge s actual shoulder and ogive geometry instead of a generic approximation borrowed from another case. For precision shooters and competitive reloaders who want measured case and cartridge dimensions rather than estimates the Redding Instant Indicator in .223 Rem is available for sale at GrabAGun. Redding Instant Indicator Specifications Brand: Redding Model: Instant Indicator Measuring Type: Instant Indicator Without Dial Indicator Reloading Caliber: .223 Rem Function: Headspace and Bullet Comparator Indicator Stem Diameter: 0.375 Available At: GrabAGun