Maintaining your AR-15 rifle requires meticulous attention to detail, and understanding headspace is paramount to ensuring safe and reliable operation. Incorrect headspace can lead to catastrophic malfunctions, so this process demands precision and caution. This guide provides a comprehensive overview of checking headspace on your AR-15, empowering you to perform this critical maintenance task safely and effectively.
Understanding Headspace and Headspace Gauges
Headspace refers to the distance between the bolt face and the breech face of the chamber when the bolt is fully closed. This crucial dimension dictates the amount of cartridge case expansion that occurs upon firing. Too little headspace (short headspace) can cause malfunctions like squib loads or failure to fire, while excessive headspace (long headspace) is incredibly dangerous. It allows the cartridge case to expand excessively, potentially causing a catastrophic case rupture, resulting in serious injury or damage to the firearm.
To accurately measure headspace, you'll need a headspace gauge. These gauges are specifically designed for AR-15s and come in "GO" and "NO-GO" configurations.
- GO Gauge: This gauge should fit smoothly into the chamber when the bolt is closed. If it doesn't, you have a potential headspace issue.
- NO-GO Gauge: This gauge should not fit into the chamber when the bolt is closed. If it does, you have excessive headspace, requiring immediate attention.
How to Check Headspace on Your AR-15
Checking headspace is a relatively straightforward process, but it requires the proper tools and a meticulous approach.
1. Gather Your Tools: You'll need your AR-15, a complete set of AR-15 headspace gauges (GO and NO-GO), a clean work surface, and potentially a bore brush and solvent (for cleaning prior to checking).
2. Prepare Your Rifle: Ensure your rifle is unloaded. Visually inspect the chamber to verify it's clear of any obstructions. Consider cleaning the chamber to remove any debris that could interfere with accurate headspace measurement.
3. Insert the GO Gauge: Carefully insert the GO gauge into the chamber. Close the bolt completely. The GO gauge should slide into the chamber smoothly. If there’s resistance, it could indicate a potential problem.
4. Insert the NO-GO Gauge: Attempt to insert the NO-GO gauge. This gauge should not fit. If the NO-GO gauge enters the chamber, it signifies excessive headspace, requiring immediate professional attention from a qualified gunsmith. Do not attempt to fire the rifle.
5. Interpretation of Results:
- GO Gauge fits smoothly, NO-GO Gauge does not: This indicates your AR-15's headspace is within the acceptable range.
- GO Gauge does not fit: This suggests potentially short headspace, which may cause malfunctions.
- NO-GO Gauge fits: This signifies dangerously long headspace, requiring immediate action.
What to Do If Headspace is Incorrect
If you determine your AR-15 has incorrect headspace (either short or long), do not attempt to fix it yourself. Incorrect headspace is a serious safety issue and requires the expertise of a qualified gunsmith. A gunsmith can accurately diagnose the problem and perform the necessary repairs or replacements.
Maintaining Proper Headspace
Regular maintenance plays a vital role in preserving proper headspace. Avoid using excessively worn or damaged parts. Ensure that your barrel is properly installed and torqued. Regular cleaning of the firearm will help prevent build-up of debris that may interfere with headspace.
This guide is intended for informational purposes only. Always prioritize safety and seek professional assistance when dealing with firearm maintenance that requires specialized knowledge. Improper headspace can lead to severe consequences, highlighting the importance of performing this check responsibly.
