Worst Ever BCG AUTOPSY caught on camera. (See description)

Published on November 22, 2021
Duration: 18:44

This video provides a detailed autopsy of a faulty AR-15 Bolt Carrier Group (BCG). The analysis reveals critical manufacturing defects including an undersized bolt tail failing gauges, excessive firing pin protrusion causing pierced primers, an oversized firing pin hole, and an oversized cam pin hole leading to headspace issues. These flaws significantly compromise the BCG's function and reliability.

Quick Summary

This AR-15 Bolt Carrier Group (BCG) has critical manufacturing defects, including an undersized bolt tail failing gauges, excessive firing pin protrusion (0.039 inches), an oversized firing pin hole, and an oversized cam pin hole causing headspace issues. These flaws severely impact its reliability and function.

Chapters

  1. 00:00Introduction: Problematic BCG Identified
  2. 01:40Bolt Tail Gauging Failure
  3. 03:50Firing Pin Protrusion Measurement
  4. 05:30Firing Pin Hole Inspection
  5. 07:15Cam Pin Hole & Headspace Check
  6. 08:54Extractor & Carrier Length Analysis
  7. 11:30Carrier Key & Alignment Test
  8. 13:00Internal Carrier Gauging Results

Frequently Asked Questions

What are the main problems found with this AR-15 Bolt Carrier Group?

The BCG exhibited an undersized bolt tail failing gauges, excessive firing pin protrusion (0.039 inches), an oversized firing pin hole, and an oversized cam pin hole leading to headspace issues. These defects compromise its functionality and reliability.

What is the significance of the bolt tail failing no-go and field gauges?

Failing these gauges means the bolt tail is undersized. This allows excessive gas to escape rearward during firing, reducing the rifle's cycling efficiency and potentially causing malfunctions.

Why is excessive firing pin protrusion a problem?

Firing pin protrusion exceeding the standard range (0.028-0.036 inches) can cause the firing pin to strike the primer too deeply or with too much force. This can lead to pierced primers, gas leakage, and potential firearm malfunctions.

How does an oversized firing pin hole affect BCG function?

An oversized firing pin hole creates a gap around the firing pin. This allows hot gases and primer material to flow back into the bolt carrier, potentially causing malfunctions and damage over time.

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