How to check ar15 Headspace without gauges?

How to Check AR-15 Headspace without Gauges: A Comprehensive Guide

Are you looking to check the headspace of your AR-15 without using a headspace gauge? It’s essential to ensure that your rifle is accurately chambered and functions correctly. In this article, we’ll guide you through the process of checking headspace without gauges, providing you with a comprehensive and step-by-step approach.

What is Headspace?

Before we dive into the process, let’s understand what headspace is. Headspace refers to the distance between the case mouth and the breech face, measured from the face of the bolt and the rim of the cartridge. In an AR-15, headspace is critical, as it determines the accuracy and reliability of the rifle.

Why Check Headspace?

Headspace is crucial in an AR-15 for several reasons:

• Accuracy: Insufficient headspace can lead to poor accuracy, as the cartridge is not seated correctly in the chamber.
• Functioning: A rifle with insufficient headspace may not extract or eject the spent cartridge correctly, leading to malfunction or jamming.
• Safety: Excessive headspace can cause the fired cartridge to become stuck in the chamber, leading to an unsafe situation.

The Process: Checking AR-15 Headspace without Gauges

To check the headspace of your AR-15 without gauges, follow these steps:

Step 1: Prepare Your Rifle

1. Clean and inspect the rifle: Ensure the rifle is clean and free of debris, oil, or any other residue that might interfere with the measurement process.
2. Chamber flag: Remove any chamber flags or other obstructions that might interfere with the measurement process.
3. Bolt carrier: Install a Chamber Flag or a 5.56mm chamber flag in the chamber to prevent the cartridge from seating too far into the chamber.

Step 2: Measure the Cartridge

1. Use a caliper or micrometer: Measure the overall length of the cartridge (case and bullet) using a caliper or micrometer. Record the measurement.
2. Case length: Measure the length of the case only (without the bullet) using a caliper or micrometer. Record the measurement.

Step 3: Calculate the Headspacing

1. Subtract case length from overall length: Subtract the case length from the overall length of the cartridge (from Step 2).
2. Calculate headspace: Add the barrel groove diameter (or chamber diameter) to the result from Step 3.1. This will give you the headspace measurement.

Example:

• Overall cartridge length: 2.250"
• Case length: 1.600"
• Barrel groove diameter: 0.700" (for an AR-15 with a .700" chamber diameter)
• Headspace calculation: 2.250" – 1.600" = 0.650" + 0.700" = 1.350"

Interpret the Results

• Within spec: If the headspace measurement falls within the manufacturer’s recommended range (typically 0.000" to 0.010"), the rifle is likely functioning correctly.
• Out of spec: If the headspace measurement is excessive (less than 0.000"), the rifle may experience issues with extraction and ejection. If the headspace is insufficient (greater than 0.010"), the rifle may experience problems with chambering and feeding.

Tips and Considerations

• Familiarize yourself with your rifle’s specifications: Understand the recommended headspace range for your specific rifle to ensure accurate measurement.
• Use a consistent and precise measurement method: Avoidusing a caliper or micrometer with a loose fit, as this may result in inaccurate measurements.
• Consult a professional: If you’re unsure about the measurement process or headspace results, consult a professional gunsmith or a qualified rifle technician.

In conclusion, checking the headspace of your AR-15 without gauges requires attention to detail, patience, and a willingness to learn. By following the step-by-step process outlined above, you’ll be able to ensure your rifle is accurately chambered and functions correctly. Remember to stay within the manufacturer’s recommended headspace range to avoid potential issues with accuracy, functioning, and safety.