Why measure headspace?

      Setting the height of your resizing die properly ensures that your handloads will have the ideal clearance (at the shoulder) in your particular chamber.   However, this means going beyond reading the instructions that came with your dies.   When your cases fit perfectly in your chamber, it extends the life of your cases by eliminating excessive brass resizing.   It can also deliver more consistent accuracy.

Why measure OAL back from the bullet ogive?

      Most bullet tips vary too much to allow accurate OAL measurements.   Measuring back from the bullet ogive gives more accurate readings, and it also exposes irregular bullet shapes and problems with inconsistent seating depth.   This gauge also helps measure your bullet "jump" to the rifling.   Solving these problems will always increase accuracy.

Operating Instructions

      This digital headspace gauge is designed to measure the "clearance" between the shoulder of your handloads and the front of the chamber in YOUR particular rifle.   You can take this measurement from anywhere on the shoulder.   This is accomplished by first measuring a case that was fired in your chamber and pressing the zero button on the digital indicator.   Then you're setup to measure your handloads, and see exactly how they compare to your "known" chamber size.   The digital indicator will then display the exact headspace clearance of your handoads in your particular chamber.   (This should not exceed .002")   This gauge provides uniform downward spring pressure, and that makes it quick and easy to get accurate measurements.   It can also measure seating depth at the bullet ogive.

  1. Place the headspace gauge on a flat, steady surface.
    (not balanced on your knee . . . . )
  2. Be sure to only measure cases that have primers seated below flush or removed.
  3. Raise the indicator on the main shaft, so that your fired case can be positioned under the adjustable V-block.   Lower the indicator until the V-block is positioned anywhere on the case shoulder, then lock the indicator in position.
  4. Then adjust the side thumb screw until the V-block rests somewhere near the center of the shoulder of your case.   Be sure that the top of the plunger stem rests about 1/4" above the indicator.   Then lock your side screw in position with the rear screw.
  5. Grasp your fired case (near the bottom), and rotate it clockwise until it is perfectly centered under the adjustable V-block.   When you see the lowest reading, press the ZERO button, then replace your fired case with one of your handloads.   The reading you get will represent the exact chamber clearance (headspace) of your handloads in YOUR rifle.
  6. If you want to set your headspace to fit in ANY chamber of the same caliber, use this same method, except compare your handloads to a factory round or a Go Gauge.   After you zero the digital indicator on a factory round, every measurement taken after that will show exactly how long (or short) your headspace is compared to the industry standard.   NOTE: Belted magnum handloads should headspace on the shoulder (not on the belt), so always compare them to a fireformed case.

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