Colt LE-901 Modular Multi-Caliber AR: A Well-Designed Failure

This guide details the process of changing the barrel and caliber on the Sig MCX Virtus platform, covering the transition between 5.56 NATO and .300 Blackout. It emphasizes the use of specific tools like a torque wrench with a limiter and highlights the importance of safety during disassembly and reassembly. The video demonstrates how the modularity of the MCX Virtus allows for quick caliber changes by swapping barrels and ensuring proper reassembly.

This guide details the process of changing the barrel on a Sig Sauer MCX, allowing for caliber conversions between 5.56mm and 300 Blackout, and outlines the disassembly and reassembly of the updated bolt carrier group following a mandatory recall. It emphasizes the use of a specific torque wrench for barrel installation and highlights the safety features of the new bolt carrier group, including a captive firing pin retaining pin and a firing pin safety. The process is presented as achievable by an intermediate gunsmith or mechanically inclined individual.

Ian McCollum, with high authority, details the modular caliber conversion process for the Colt LE-901-16S. The guide covers the removal of the 7.62 upper and magwell adapter, followed by the installation of the 5.56 adapter and upper, highlighting the proprietary components required for this multi-caliber functionality.

This video showcases the Q "The Megafix" rifle, a lightweight magnum powerhouse featuring a .300 Win Mag chambering and an 18-inch Proof Research barrel. Expert insights are provided on its modular design, including an AR-style control interface and a 45-degree bolt throw. The demonstration highlights a unique quick-change barrel system, allowing for rapid barrel swaps by loosening a few screws. Live fire testing by Classic Firearms confirms its potent performance despite noticeable recoil.

Roy Huntington, an expert reloader with decades of experience, reviews the RCBS MatchMaster Multi-Cartridge Reloading Block. He highlights its superior stability and multi-caliber capacity compared to traditional wooden blocks, which often lead to case instability and powder spills. The block's machined aluminum construction, non-slip feet, and tiered hole design significantly improve the reloading workflow and safety.

This video focuses on the Bushmaster ACR rifle, detailing its field stripping process. The description notes the ACR's potential for modularity but suggests it underperformed in the market due to its high price. The content aims to provide insight into the rifle's internal mechanics and assembly. Thanks are given to Ventura Munitions for supporting the video, and viewers are encouraged to support TFBTV via Patreon.

This guide details the specific technique for separating two MAS-36 rifles that have been inadvertently locked together by their bayonets. It outlines the historical context of this issue, the modification made to the bayonet to resolve it, and the step-by-step procedure for disengagement. The technique requires precise alignment and the use of a pointed tool to access the internal release mechanism, as demonstrated by firearms expert Ian McCollum.

This guide details the loading and firing procedure for the M134 Minigun, as explained by Ian McCollum. It covers manual indexing of the barrel cluster, feeding the ammunition belt, engaging controls, and firing. The guide also touches upon the weapon's spin-down inertia and the function of modern clutch systems. Expert instruction from a recognized firearms historian highlights the technical aspects of operating this powerful weapon system.

This guide details the operational features of the H&K G11 K2, a prototype assault rifle known for its caseless ammunition and unique rotating drum bolt. It covers the selector settings, magazine capacity, integrated optics, and the internal action designed for recoil management during high-rate-of-fire bursts. Expert insights from Ian McCollum highlight the historical context and technical innovations of this advanced firearm.

This guide details the operation of the German L.Gr.W.36 50mm light mortar, as demonstrated by expert Ian McCollum. It covers assembly, leveling procedures, ammunition handling, and live fire execution, emphasizing the difficulty in visually tracking the projectile. The instruction highlights the importance of proper setup for accuracy.