Understanding the Importance of Headspace
The AR-15 and its Role in Firearms Culture
The AR-15 platform has become a cornerstone of American firearm ownership, admired for its modularity, versatility, and widespread availability. From the casual plinker to the competitive shooter, many individuals find the AR-15 to be a reliable and adaptable rifle. However, like any mechanical device, proper maintenance is essential to ensure optimal performance and, crucially, safety. A critical aspect of AR-15 maintenance that often gets overlooked is headspace. Understanding and properly addressing headspace is paramount to maintaining the rifle’s accuracy and, more importantly, to preventing potentially dangerous malfunctions. This comprehensive guide will delve into the world of AR-15 go no go gauges, clarifying their function, their importance, and how to properly use them to keep your firearm operating safely and effectively.
Why Headspace Matters
The AR-15’s popularity stems from its ease of customization and its role in many shooting disciplines. This often leads owners to modify their rifles, swapping barrels, bolts, or other components. Each component’s performance and longevity depend on the tight tolerances inherent in firearm design. One of the most critical tolerances is headspace, the distance between the bolt face and the base of the chambered cartridge. This distance is precisely measured and controlled during the manufacturing process, but changes can occur due to wear, damage, or improper component installation. If headspace is incorrect, the potential for dangerous malfunctions arises.
The Risks of Improper Headspace
Headspace is more than just a measurement; it is a key factor in the safe operation of your AR-15. When the headspace is too short, the cartridge cannot fully seat within the chamber. If the firearm is fired under these conditions, pressure can quickly build up, potentially causing the cartridge to rupture, leading to serious injury to the shooter and/or damage to the firearm. Conversely, if the headspace is too long, the case expands excessively during firing, which can lead to case separation, a malfunction where the case rips apart, leaving the rear portion of the cartridge stuck in the chamber. This also presents a risk to the shooter. The effects of incorrect headspace range from a failure to fire to catastrophic component failure, making this measurement a key safety and performance factor.
Headspace Standards for .223/5.56 Rifles
For .223 Remington/5.56x45mm NATO AR-15 rifles, the standard headspace dimensions are precisely specified. This ensures proper cartridge ignition, expansion, and extraction. Deviating from these specifications, even slightly, can cause significant problems. It’s essential to understand that a properly functioning AR-15 requires these tolerances to be within the design specifications for safe and reliable operation. This understanding leads us to the critical tools for ensuring a rifle operates within these limits: go no go gauges.
Introducing the AR-15 Go No Go Gauge
Purpose and Function
At its core, the concept of headspace requires a way to confirm the distance between the bolt face and the chamber base is within the allowable safe limits. The AR-15 go no go gauge provides this precise and simple means of checking. These tools are specifically engineered to allow a gun owner to quickly and easily verify whether their rifle’s headspace falls within acceptable limits. Using these gauges is a crucial, preventative maintenance step, which can avert some of the most catastrophic issues which can arise.
Components and Materials
An AR-15 go no go gauge is essentially a set of precision-machined “dummy cartridges” representing the minimum and maximum acceptable chamber dimensions. They’re typically made of hardened steel to ensure durability and accurate measurements over time. These gauges are engineered to fit within the chamber in a way that simulates the cartridge’s interaction with the bolt face. They’re not complicated tools, but their precision makes them invaluable for gun owners concerned with safety and performance.
Understanding the Gauge Set
The go no go gauge set typically consists of the following: the “Go” gauge, the “No-Go” gauge, and sometimes a “Field” gauge. The “Go” gauge, as its name implies, is designed to ensure the bolt will close completely and function properly on a cartridge within specification. The “No-Go” gauge, is slightly longer than the maximum acceptable headspace. If the bolt closes on the “No-Go” gauge, the headspace is too long, indicating a potential safety issue. The “Field” gauge, if included, represents the maximum allowable headspace before the rifle is considered unsafe for use. The Field gauge serves as a clear indication of when the rifle should be removed from service for repair.
How to Use AR-15 Go No Go Gauges
The Step-by-Step Process
Understanding how to use these gauges is essential. First, the bolt carrier group is usually separated from the upper receiver. Before proceeding, safety is paramount. Always make sure the rifle is unloaded and the magazine is removed. Visually and physically inspect the chamber to ensure that there is no ammunition present. With the bolt carrier group removed, insert the “Go” gauge into the chamber. Now, gently close the bolt carrier group on the gauge. It should close fully and easily. If the bolt fails to close completely, there may be an issue with the rifle or the gauge, or with the components, that requires further investigation.
The Importance of Safety
Next, remove the “Go” gauge and insert the “No-Go” gauge into the chamber. Again, gently close the bolt. If the bolt carrier group closes completely and locks on the “No-Go” gauge, it means the headspace is too long and out of the specified range. The rifle should not be fired until this problem is resolved. This is a crucial step in evaluating the headspace. Closing on this gauge indicates the potential for cartridge case separation. The case may stretch beyond its limits, and that’s a potential danger.
Using the Field Gauge
The “Field” gauge, if available, is used as a final check. If the bolt closes on the Field gauge, it means the headspace is beyond the maximum tolerance and the rifle is considered unsafe for use. When the Field gauge is used, the rifle will need immediate attention by a qualified gunsmith.
Benefits of Proper Headspace Checks
Using this system is simple to learn, but it can prevent serious and costly problems. The step-by-step process allows a gun owner to check the chamber, quickly confirming that the headspace is within the specification for that particular rifle.
Troubleshooting and Solutions
Addressing Failing Gauge Tests
If your rifle fails the headspace gauge test, it is crucial to avoid firing the weapon until the issue is addressed. The first step is often the simplest: thoroughly inspect the chamber for any debris that might be obstructing the complete closure of the bolt. Ensure that the bolt is properly assembled and that all parts are present and correctly oriented. Check to verify that the gauge is actually for the correct caliber. Different calibers will not be correctly verified with the wrong gauge.
Potential Causes and Remedies
If these simple checks don’t resolve the issue, the problem likely lies with the barrel, bolt, or both. Worn or damaged barrels or bolts can cause incorrect headspace. Sometimes, a new barrel is all that’s needed, while at other times, replacing the bolt may be the better course of action. It’s also possible that improper installation is to blame, particularly when dealing with aftermarket components. A qualified gunsmith is best suited to diagnose and resolve these issues, and their experience and expertise will provide the best results. Never attempt to modify or repair your rifle if you are not properly trained and equipped to do so.
Purchasing and Maintaining Headspace Gauges
Choosing the Right Gauges
Choosing and maintaining your headspace gauges requires some consideration. Purchasing a set of quality gauges is an investment in your rifle’s safety and longevity. Opt for gauges made from hardened steel or similar durable materials. These gauges will withstand the rigors of repeated use. Make sure to select the appropriate gauges for the specific caliber of your AR-15, as different calibers require different headspace specifications.
Where to Buy Headspace Gauges
You can purchase these gauges from a variety of sources. Many online retailers specializing in firearms accessories offer a wide selection. Local gun stores are also a good source. Consider the reputation of the manufacturer and read online reviews to get an idea of product quality and customer satisfaction. A trustworthy gauge set will last for many years if properly maintained.
Caring for Your Gauges
To maintain your headspace gauges, always clean and store them in a safe, dry environment after each use. Protect them from rust, corrosion, and physical damage. Proper storage will extend their lifespan and preserve their accuracy.
Importance of Regular Headspace Checks
Regularly checking your AR-15’s headspace is a proactive measure that can prevent serious problems. Consider it part of your standard maintenance routine. Many owners check it every time they clean their rifle or change barrels or bolts. It is much less expensive to deal with any issues before a problem develops. This is a key part of responsible firearms ownership.
Common Mistakes and Helpful Tips
Errors to Avoid
The most common mistakes in using headspace gauges are often related to user error. Ensure the rifle is unloaded before beginning any work. Failure to properly disassemble the rifle can lead to incorrect readings. Forcing the bolt on a gauge can damage both the gauge and the rifle. Always take your time, and follow the steps carefully.
Seeking Professional Help
Always consult with a professional if you are unsure about any step. Always double-check your measurements. There is no substitute for a qualified gunsmith when dealing with complex firearm problems. These professionals have the necessary expertise and equipment to accurately diagnose and resolve headspace issues.
Conclusion: Prioritizing Safety and Accuracy
The Importance of Gauges
In conclusion, AR-15 go no go gauges are a critical tool for anyone who owns and maintains an AR-15. Understanding headspace and using the appropriate gauges is essential to ensure the safe and reliable operation of your firearm. From preventing malfunctions to increasing the longevity of your rifle, the small effort required to check headspace is well worth it.
The Value of Headspace Checks
Remember the importance of the headspace in ensuring a safe and accurate shooting experience. By following the guidelines in this guide, you can protect yourself and others from the potential hazards associated with improper headspace. Checking the headspace is not complicated, but its importance cannot be understated. Make it a regular part of your routine.
Final Thoughts
You can easily find go no go gauges online at numerous retailers. Invest in a quality set today. Start checking your AR-15’s headspace before every range trip. Your safety, and the safety of those around you, depend on it. Consider this an essential part of responsible gun ownership and a key step in maximizing your rifle’s accuracy and reliability for years to come. Don’t hesitate to consult a qualified gunsmith if you encounter any difficulties or have any questions. They are available to provide assistance and ensure your firearm is operating safely and effectively.
