Introduction:
The 5.56 NATO cartridge is a staple in modern military and civilian firearms. Ensuring the proper chamber dimensions is crucial for reliable function and safety. This is where the go no-go gauge 5.56 comes in. This essential tool allows gunsmiths and firearm enthusiasts to precisely measure the chamber's dimensions, confirming its suitability for the 5.56 round. This post delves deep into the world of go no-go gauges, specifically focusing on their use with the 5.56 caliber. We'll cover what they are, how they work, and why they're vital for safe and reliable firearm operation. We'll even touch upon some common mistakes to avoid.
Understanding Go No-Go Gauges
Go no-go gauges are precision-machined tools used to inspect firearm chambers. They come in pairs: a "go" gauge and a "no-go" gauge. Both are shaped to precisely match the dimensions of a specific cartridge, in this case, the 5.56x45mm NATO.
- Go Gauge: This gauge should smoothly and easily enter the chamber. If it doesn't, there's a problem.
- No-Go Gauge: This gauge should not enter the chamber fully. It's slightly larger than the "go" gauge, representing the maximum acceptable chamber dimension. If it enters easily, the chamber is excessively enlarged and dangerous.
Why Use a Go No-Go Gauge for 5.56?
Using a 5.56 go no-go gauge is crucial for several reasons:
- Safety: An improperly sized chamber can lead to dangerous situations like bullet setback, where the bullet is pushed back into the cartridge case under pressure, potentially causing catastrophic failure.
- Reliability: A chamber that's too tight or too loose can cause malfunctions, including failure to feed, chamber, or extract rounds.
- Accuracy: While less direct, a properly sized chamber contributes to improved accuracy.
- Legal Compliance: Some jurisdictions require chamber inspections for specific firearm modifications or transfers.
How to Use a 5.56 Go No-Go Gauge
Using these gauges is straightforward, but precision and safety are paramount. Here's a step-by-step guide:
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Clean the Chamber: Thoroughly clean the firearm's chamber before using the gauges to avoid debris interfering with the measurements.
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Insert the Go Gauge: Gently insert the "go" gauge into the chamber. It should slide in smoothly and easily without any resistance. If it encounters resistance, the chamber is likely too tight.
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Insert the No-Go Gauge: Now, attempt to insert the "no-go" gauge. It should not enter fully. If it enters easily, the chamber is too large. A slight resistance is acceptable. The gauge should stop short of the case head.
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Interpretation:
- Both gauges slide in easily: The chamber is excessively enlarged and dangerous. Do not use the firearm until it's repaired or replaced.
- The "go" gauge slides in smoothly, and the "no-go" gauge doesn't: The chamber is within acceptable limits.
- The "go" gauge encounters resistance: The chamber may be too tight, potentially requiring attention from a gunsmith.
Common Mistakes to Avoid
- Using the Wrong Gauge: Ensure you are using a gauge specifically designed for the 5.56x45mm NATO cartridge. Using the incorrect gauge can lead to inaccurate readings.
- Forcing the Gauges: Never force a gauge into the chamber. This could damage the gauge or the firearm.
- Ignoring Results: Always take the gauge readings seriously. If the chamber is out of specification, do not use the firearm until it's corrected by a qualified gunsmith.
Case Study: Identifying a Problematic Chamber
A gunsmith received a rifle for service that exhibited repeated feeding issues. Using a 5.56 go no-go gauge, he found that both gauges slid in smoothly. This confirmed that the chamber was excessively enlarged, likely due to improper headspacing or wear. The gunsmith repaired the chamber, resolving the feeding problems and ensuring the firearm's safety.
Conclusion
The 5.56 go no-go gauge is an indispensable tool for anyone working with 5.56 firearms. By using this gauge correctly, you ensure safe and reliable operation. Regular inspections, particularly after significant use or modifications, are crucial for maintaining the firearm's integrity and safety. Remember, always prioritize safety and seek professional help if you encounter any issues. Don't hesitate to consult a qualified gunsmith if you're uncertain about any aspect of this process. Ignoring proper chamber dimensions can have serious consequences.