M203 Underbarrel Grenade Launcher

This guide details the operation of the M16A1 rifle with an M203 grenade launcher attachment, drawing on expert instruction from Brandon Herrera. It covers manual of arms for both components, loading procedures, firing techniques for both 5.56x45mm NATO and 40mm rounds, and emphasizes the importance of understanding NFA classifications for such devices. The instruction highlights how the weight of the M203 aids in controlling full-auto fire.

This entry details the Colt XM-148, an early under-barrel grenade launcher developed for the M16 rifle during the Vietnam War. It covers its development context within Project SPIW, its operational mechanics including loading and cocking, and the reasons for its eventual replacement by the M203. The information is presented with high authority by Ian McCollum of Forgotten Weapons, highlighting deep knowledge of US military small arms programs.

This guide details the installation and basic operation of underbarrel grenade launchers for the British SA80 weapon system, covering both historical Enfield adaptations and the modern Heckler & Koch AG SA80. It emphasizes proper attachment, familiarization with loading and sighting mechanisms, and crucial safety checks. The information is presented with the technical detail expected from an expert instructor like Ian McCollum.

This video provides a practical demonstration of the Heckler & Koch MR556 A1 rifle, showcasing its operation with an underbarrel M203-style grenade launcher. The content highlights safe and proficient handling, including rapid fire, magazine changes, and grenade launcher deployment. The demonstration is conducted by FrenchGunGuy, a high-level firearms enthusiast, on an outdoor shooting range.

This entry details the installation of a TDI foregrip onto an M203 grenade launcher, as seen on an IDF rifle from the Alexandroni Brigade. It highlights the use of a Meprolight GLC for the launcher and an M5 optic. The guide emphasizes safety during accessory mounting.

Palmetto State Armory showcased the Sabre Key, an under-barrel 12 gauge shotgun, at SHOT Show 2026. This Short-Barreled Shotgun (SBS) utilizes a proprietary M203-style mounting system compatible with M4A1 profile AR-15 barrels. Thanks to NFA tax changes and a partnership with Capital Armory, it can be shipped directly to consumers. Production is slated to follow the release of the 570 pump and semi-auto models.

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.