The United States’ quest for a repeating firearm action grenade launcher during the Vietnam War resulted in various models in hopes of coming up with a reliable and capable squad-level one. Before the China Lake grenade launcher, what were considered the successful ones were the M79 and XM148. Even so, the performance of the two was far from satisfactory, especially in terms of the sought-after pump action power.

M79 and XM148

The M79 grenade launcher was made after World War II as a result of the dissatisfaction of the US Army with its regular rifle grenades with its insufficiency with general-purpose fire support capabilities. Through what they labeled Project Niblick, the US Army attempted to increase firepower through an explosive projectile more accurate than rifle grenades with a different range and more portable mortar.

The M79 was used during the Vietnam War and effectively defeated enemies and outpaced Viet Cong’s commando mortars. Different variants of the 40 mm rounds had also been produced, like the M381 HE (High Explosive) round, M576 Buckshot round, and M1006 less-lethal round (fires a foam rubber projectile), to name a few. However, the main issue was that it was limited to a single round fired and required manual reloading of the weapon after each shot.

United States Army Heritage and Education Center, Public domain, via Wikimedia Commons

XM148 was another wartime development used by the US Special Forces along with the XM177E2. Colt Firearms also manufactured it as a launcher for field testing during the Vietnam War. 

Problems XM148 was, aside from being a single round fire, its extended trigger caused frequent accidental discharges as it usually gets caught on gears, tree branches, and literally anywhere. This design was intended so users could fire without removing their hands from the pistol grip. Evaluations were made, but XM148 never made it into service. Imagine the hassle of fighting in the dense Vietnam jungle with your launcher’s trigger getting caught up on every vein and branch you pass. Later on, its concept would be the foundation of the M203 we know today.

China Lake 40mm Grenade Launcher

As America’s involvement in the Vietnam War increased, the need for specialized weapon systems, especially for Navy SEALs, arose. This was when China Lake Naval Air Weapons Station entered the scene. 

China Lake Naval Air Weapons Station was established during World War II under the United States Navy. Its purpose was to support the US Navy’s research, development, acquisition, testing, and evaluation of weapons systems for the soldiers. 

During the Vietnam war, they were tapped to produce a more reliable grenade-launching system that would outperform the M79 and XM148. China Lake began working in 1967, spearheaded by Alfred Kermode. The result was what was known as the China Lake Grenade Launcher.