The History of the Colt External Piston System

This video compares the operating system of an Adams Arms piston-driven AR-15 to the AK-47's direct impingement system. It highlights how the piston system, using a reciprocating rod, keeps the bolt carrier group cleaner by venting gas and fouling away from the receiver. This design is noted as being particularly beneficial for suppressor use due to reduced gas blowback.

This expert review by Military Arms Channel provides a deep dive into the Sig Sauer 516 G3, highlighting its significant upgrades over previous models and its influence from the HK 416. The analysis focuses on enhanced durability features like replaceable steel pins and radiused bolt lugs, modularity with a swappable forward assist, and a refined 4-position gas system. The review also includes practical shooting impressions and accuracy testing with various ammunition types, positioning the 516 G3 as a high-value piston-driven AR platform.

This review of the PWS MK116 Mod 2 AR-15 focuses on its longstroke gas piston system, comparing it to short-stroke systems and direct impingement. The reviewer highlights its cleaner operation, predictable recoil, and ease of tuning for suppressed use, while also noting potential cons like proprietary parts and a stiffer safety selector. The rifle is presented as a well-valued option in its price tier, offering sub-MOA accuracy potential and reliable performance across various ammunition types.

This review of the Brownells BRN-180 Gen 3 piston upper receiver highlights significant improvements over previous generations, focusing on enhanced reliability and user-friendly features. Key upgrades include a toolless adjustable gas system with distinct settings for standard, adverse, and suppressed use, a full-length steel shield in the upper receiver for protection, and an improved left-side charging handle. The review also touches on barrel enhancements for suppressor mounting and initial accuracy testing.

This video from The VSO Gun Channel reviews the Adams Arms complete AR-15 piston upper receiver, comparing it to traditional direct impingement (DI) systems. The instructor highlights the primary benefit of piston guns: running cleaner by venting hot gas away from the receiver. The review details the Adams Arms system's design, including its monolithic MLOK rail, adjustable gas block with a set screw for fine-tuning, and a robust piston rod mechanism. While praising its clean operation and solid construction, a minor critique is offered regarding the small size of the gas block's set screw.

This video provides a first look at the Bear Creek Arsenal (BCA) GPx Piston Upper, potentially the most affordable piston AR upper on the market. The review highlights its similarities to Superlative Arms components, particularly the BCG and adjustable gas block. Initial shooting impressions indicate it functions well, though adjustment requires removing the handguard, and light primer strikes were observed with certain steel-cased ammunition.

This video offers a highly critical, historically grounded analysis of the M14 rifle's shortcomings, attributing its failure to flawed US Ordnance Corps decisions regarding cartridge standardization and weapon design. The speaker, an expert in small arms, details how political motivations and resistance to innovation led to the adoption of an inadequate weapon system, contrasting it with superior alternatives like the AR-10 and FN FAL. The analysis highlights the detrimental impact of these decisions on US military effectiveness, particularly in Vietnam.

This expert-level entry details the M16's troubled introduction in Vietnam, debunking myths of inherent design flaws. It highlights how political decisions, procurement issues, and ammunition choices, rather than the core design by Eugene Stoner, led to early reliability problems. The entry emphasizes the mechanical evolution from the AR-15 to the M16A1 and the critical role of chrome lining, proper maintenance, and correct ammunition in establishing the platform's eventual success.

This guide, drawing on the expertise of a former Colt employee and AR-15 SME Hank Tatro, details the critical role of AR-15/M16 buffers. It explains how buffer design evolved to manage bolt carrier bounce caused by increased firing rates and different ammunition types. The guide emphasizes selecting the correct buffer for specific firearm configurations and warns against improper mixing and matching, particularly for duty applications. It covers standard rifle and carbine buffers, as well as H, H2, H3, and specialized 9mm buffers, providing insights into their construction and application.

This comprehensive review by Chris Bartocci, a recognized expert with extensive military armory experience, debunks common myths surrounding the Beretta M9/92FS. Bartocci details the pistol's history, including its selection over the M1911, and addresses controversies like slide failures, attributing them to ammunition and high usage rather than design flaws. He highlights the evolution of critical components like the locking block and discusses magazine reliability issues, offering practical insights for owners and enthusiasts.