2 KAK BCG's - Bent/Damaged Extractor Pins

This video from School of the American Rifle highlights critical manufacturing defects in AR-15 bolt carrier keys, specifically focusing on rough internal bores. Lead instructor demonstrates how a poorly finished carrier key can cause significant friction, premature wear on components like gas tubes, and operational issues, contrasting a problematic new Colt carrier with a well-functioning older model. The expert emphasizes the importance of a smooth bore for reliable function and longevity of expensive parts.

This video details issues encountered with a Noveske N4 Switchblock rifle, initially intended as a full review. The creator experienced operational problems, seemingly self-inflicted, leading to a departure from the planned review format. The focus shifts to troubleshooting and identifying the root cause of the malfunctions, which included the bolt carrier not holding under its own weight. The creator consulted with Noveske, who were also perplexed. A new bolt was ordered to test for a solution. Despite the initial problems, the rifle is now running well, which the creator attributes to potential manufacturing tolerance differences. A follow-up video is promised to confirm resolution and provide a final assessment.

This video demonstrates the cleaning and restoration of a heavily fouled Daniel Defense Bolt Carrier Group (BCG) using the Tactical Elites gun cleaning kit. It covers step-by-step disassembly, thorough scrubbing to remove carbon buildup, and meticulous reassembly. The process highlights the importance of proper firearm maintenance for preserving component integrity and functionality, showcasing the effectiveness of the cleaning kit.

This guide details the evolution of AR-15 carrier key staking from early 'Gen 1' square staking to modern 'Gen 5' OCKS with serrated heads. It emphasizes proper torque values (vintage 35-40 in-lbs, modern 55-58 in-lbs) and the importance of sufficient metal displacement for screw security. The video, presented by an expert from School of the American Rifle, critiques commercial staking and references historical technical manuals.

This video explains how to check and replace the gas rings on an AR-15 bolt carrier group. A simple 'stand test' can indicate worn rings. The process involves disassembling the bolt, removing old rings with a pick, and installing new ones, ensuring the gaps are staggered to prevent gas leakage. Proper staggering is crucial for optimal firearm function.

This YouTube Short demonstrates the correct procedure for lubricating a Bolt Carrier Group (BCG), a critical maintenance task for AR-15 style firearms. The video aims to educate viewers on proper lubrication techniques to ensure optimal firearm performance and longevity. The title suggests a challenge to established methods, implying a definitive or improved approach to BCG lubrication.

This video details the diagnosis and repair of a feeding issue on a Sons of Liberty Gun Works East India upper receiver. The root cause was identified as a sharp burr on the barrel extension's feed ramp, causing rounds to jam. The solution involved polishing the feed ramps and adding a secondary bevel, replicating Colt's design, which successfully resolved the malfunction.

This video demonstrates the internal mechanics of an AR-15 bolt carrier group using cutaway models. It highlights the importance of internal bore dimensions for gas system efficiency and explains how to diagnose potential issues like gas leaks. The demonstration covers the cycle of operation, critical seals, and common manufacturing defects, offering advanced insights for AR-15 maintenance and troubleshooting.

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.

This video demonstrates a specialized technique for swapping an AR-15 rear takedown pin without full firearm disassembly. It highlights the use of a custom-fabricated tool, often made from a 1/16 inch Allen wrench, to depress the detent. The method allows for efficient pin replacement, particularly useful on rifles with staked castle nuts, by leveraging the old pin to guide the new one into place.