AR15 Upper Receiver Visual Checks/Inspections

This video from AT3 Tactical explores the function and necessity of the forward assist on AR-15 style firearms. It delves into the component's historical origins, specifically its introduction during the Vietnam War era, and examines its practical applications and potential drawbacks on modern rifles. The content aims to educate viewers, whether they are new to building or modifying AR-15s, to make an informed decision about the forward assist's role in their firearm setup. The video also touches on specific drills and potential problems associated with the component.

Elliott Delp showcases his favorite AR-15 build, a compact and mobile SBR emphasizing both aesthetics and functionality. The build features a Daniel Defense upper receiver known for reliability, paired with traditional A2 sights and modern accessories like a vertical foregrip and red dot optic. Live-fire demonstrations highlight its performance and manageable recoil.

This guide details the reassembly process for the Ruger Harrier Rifle, emphasizing critical safety precautions. It covers the step-by-step installation of the bolt, bolt carrier, cam pin, firing pin, charging handle, and the joining of upper and lower receivers. The instructions are delivered with expert clarity, ensuring proper function and safe operation after reassembly.

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 guide details the process of diagnosing and fixing a significant rail wobble issue on a new Daniel Defense Mk18 upper receiver. The primary cause identified was a hand-tight barrel nut, compromising the stability of the RIS II rail system. The steps involve disassembly, inspection of the barrel nut, proper tightening with an armorer's wrench and torque wrench, and reassembly. This addresses a critical quality control failure that can affect firearm accuracy and reliability.

This YouTube video, titled 'Do you still run an old charging handle?', appears to be a discussion or review focused on firearm components, specifically charging handles. Given the title, it likely explores the utility, performance, or perhaps upgrades related to charging handles, potentially comparing older designs with newer ones. The content could delve into functionality, ergonomics, or compatibility with various firearm platforms.

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.