Dual Ejector AR Bolts - The Good and the Bad

This expert guide from the School of the American Rifle details how to identify and address rough carrier key bores in AR-15 bolt carrier groups. The instructor, demonstrating expert knowledge, explains how these manufacturing defects, particularly on Colt components, can lead to premature wear on the gas tube and reduced reliability. Solutions involve replacing the defective carrier key to ensure smooth operation and longevity of the firearm.

This guide details the installation and function of the SpeedTac Bolt Carrier, highlighting its design to eliminate magazine tension during closed-bolt reloads. The video emphasizes this as a significant advancement for AR-15 platforms, potentially offering a competitive edge. The presenter, with an instructional and experienced tone, suggests this feature should be standard on all AR-style rifles.

This guide provides expert-level troubleshooting steps for common issues encountered with 300 Blackout FRT (Firearm Research & Technology) setups, drawing on hands-on testing and component analysis. It covers buffer weight, spring selection, ammunition variability, suppressor interaction, and feed ramp polishing, offering practical solutions for achieving reliable function. The instruction emphasizes a methodical approach to diagnosing and correcting malfunctions in direct impingement AR-15 platforms chambered in .300 Blackout.

This guide details how to inspect an AR-15 Bolt Carrier Group (BCG) for critical defects, specifically peening marks on the carrier rails. Instruction from School of the American Rifle highlights how improper peening can lead to significant damage to the upper receiver. Proper inspection is crucial for ensuring BCG longevity and firearm safety.

This guide details the process of replacing the buffer and spring assembly in an AR-15 platform rifle. It covers disassembly, removal of the old components, installation of new parts like the Kynshot RB5000 hydraulic buffer or the Geissele Super 42 system, and reassembly with a function check. The video emphasizes proper technique and the benefits of upgraded components for recoil management and reliability.

This guide details the technical modifications involved in the Colt MARS PDW project, a miniaturized M4 variant chambered in a unique 5.56x30mm cartridge. It highlights the extensive part alterations, including receivers and internal components, and explains the rationale behind Colt's decision to shelve the project. The revival by Centurion Arms is also noted. Instruction is provided by Chris Bartocci, a recognized expert on the AR-15/M16 platform.

This guide details the process of diagnosing and repairing an owner-induced feeding problem in an AR-15 upper receiver, specifically addressing a burr on the barrel extension's feed ramp. Expert gunsmith Chad Albrecht demonstrates meticulous inspection, burr removal, and polishing techniques to restore reliable feeding. The video emphasizes that such modifications, while often overlooked, are valid solutions for specific AR-15 malfunctions.

This guide details a diagnostic technique for AR-15 bolt carrier groups, focusing on efficiency rather than simple pass/fail. Developed by Chad Albrecht of School of the American Rifle, it uses custom gauges and cutaway components to illustrate gas dynamics, critical seals, and potential failure points like gas leaks. This advanced method helps troubleshoot functionality issues and understand the nuances of the AR-15's internal gas system.

This video provides a critical, expert-level inspection of a problematic AR-15 Bolt Carrier Group (BCG) by Chad Albrecht of School of the American Rifle. The analysis details numerous manufacturing defects, including an undersized bolt tail, excessive firing pin protrusion, oversized firing pin and cam pin holes, and a failing headspace check. The content highlights the importance of precision gauging in identifying critical failure points that impact rifle reliability and safety.

This guide details a specialized technique for swapping an AR-15 rear takedown pin without requiring a full disassembly. It leverages insights from Chad Albrecht of School of the American Rifle, emphasizing the use of a modified 1/16 inch Allen wrench or a specialized tool to manage the detent. This method is particularly useful for AR-15 variants with collapsible stocks, offering a more efficient approach to maintenance.