Part 4 - Physical/Autopsy/Test Firing a 60 year old Armalite/Colt 601 AR15 Parts Kit

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 addresses a common issue encountered when using .22 Conversion kits with AR-15 platforms, where manufacturing variances can cause compatibility problems. The "Quarter Trick" is presented as a simple and inexpensive solution to rectify these issues. The video encourages viewers to become CMMG Insiders for updates on new releases and provides links to CMMG's website, Instagram, and Twitter for more information and engagement.

This video explores seven affordable upgrades for the AR-15 platform that are effective and worth the investment. It covers a range of accessories and modifications, including slings, triggers, charging handles, rail covers, foregrips, hand stops, grip tape, and even custom paint jobs. The content aims to provide practical advice for AR-15 owners looking to enhance their firearm's functionality and aesthetics without breaking the bank, catering to both new and experienced builders seeking to improve their rifle.

This YouTube video, titled 'Fazendo upgrade na minha AR15' (Making upgrades to my AR15), focuses on modifications and enhancements for the AR-15 platform. While the description is minimal, the title clearly indicates a gunsmithing or custom build theme revolving around this popular rifle. Viewers can expect content related to improving an AR-15, potentially showcasing new parts, installation processes, or performance improvements.

This video focuses on the process of upgrading an AR-15 rifle. While the description is brief, the title clearly indicates modifications and potential part installations. This type of content typically appeals to firearm enthusiasts interested in customization, gunsmithing, and improving their shooting platforms. Viewers can expect insights into available upgrades and how they might enhance performance or aesthetics.

This AR-15 upgrade focuses on enhancing homestead defense capabilities. Key modifications include installing an Ultradyne Apollo muzzle brake for improved follow-up shots, F.A.B. Defense furniture like the RAPS stock and Gradus grip for stability, and a Rise Armament Iconic two-stage trigger for precision. The build is completed with a Devil Dog Concepts side charging handle and a Winchester Supreme Optics THSX 640 thermal sight, along with F.A.B. Defense offset irons and a Spike bipod.

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.