Headspace

What headspace is, what the gauges actually mean, and how to measure the number in inches instead of collecting pass/fail verdicts.

Firearms

Headspace · Deep Dive

Headspace

SAAMI defines two dimensions. The industry sells three gauges. That gap is the whole subject.

What headspace is, what the gauges actually mean, and how to measure the number in inches instead of collecting pass/fail verdicts.

Photo: Go & No-Go gauge by Krakuspm · CC BY-SA 3.0

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    Volumes

    1. Vol 1 What Headspace Is, and Why the Number Matters More Than the Verdict
    2. Vol 2 The Four Breeching Types, and the Datum That Makes a Cone Measurable
    3. Vol 3 Reading SAAMI — Where the Numbers Actually Come From
    4. Vol 4 GO, NO-GO and FIELD — In Full, Including the Part Nobody Mentions
    5. Vol 5 Using the Gauges — The Physical Procedure, Action by Action
    6. Vol 6 Measuring the Actual Number — The Feeler-Gauge Stack
    7. Vol 7 Measuring the Actual Number — Comparators and Dial Instruments
    8. Vol 8 Chamber Casting, Direct Metrology, and What a Cast Cannot Tell You
    9. Vol 9 The Bolt-Face End — Why Headspace Is a Property of the Whole Action
    10. Vol 10 Headspace for Reloading — Case Headspace and Shoulder Bump
    11. Vol 11 Trimming, and the Correction Most Reloaders Need
    12. Vol 12 Reading Fired Brass — The Only Witness to What Happens Under Pressure
    13. Vol 13 Corrective Work — What It Takes to Change a Number
    14. Vol 14 Cheatsheet — Laminate-Ready