The China Lake Model (or China Lake pump-action grenade launcher) is a pump-action grenade launcher that was developed by the Special Projects Division of the China Lake Naval Weapons Center, which provided equipment to Navy SEALS.
The M79 and XM148 grenade launchers were single-shot, and the repeating T148E1 grenade launcher was unreliable, so a request was made to China Lake engineers. Navy SEAL teams were pleased with the resultant pump-action grenade launcher, since the tubular magazine held three 40x46mm grenades, and so with one grenade in the chamber, four grenades could be fired rapidly before reloading. In fact, a skilled operator could fire four aimed shots before the first one landed. The grenade launcher was extremely light for its size, since a significant portion of it was made of aluminum. Despite this advantage in firepower, it did have limitations as it could not reliably feed the more oddly-shaped 40mm grenades.
The pump-action grenade launcher features leaf iron sights similar to the M79. The front sight is a fixed square notch. Depending on if the leaf is folded or not, the rear square notch is either fixed or adjustable from 75 to 400 m in 25 m increments.
Though meant for SEAL teams, a handful were used by Marine Force Recon and Army 5th Special Forces Group.
Sources differ as to how many weapons were produced. One claims that between 20 and 30 were made. However, according to another source, only 16 were made. The highest original receiver number found is 50, but it may never have been made into a functional weapon. Noted SEAL historian, Kevin Dockery has confirmed 22 completed guns being carried on navy records. Currently, only four originals remain under US Navy control. It is sometimes mistakenly referred to as the "EX-41" or as the "China Lake NATIC". The EX-41 was a design prototype created in the mid-1990s based upon the earlier China Lake Model pump 40mm. The EX-41 was only produced as a single prototype. It was a follow on design created a full two decades after the China Lake Model was produced. The China Lake NATIC designation is also erroneous as the weapon was never known by that designation. Since it was made on an ad hoc basis for special operations forces, it was not formally adopted and has no official designation. Thus the SEALs referred to the experimental weapon by referencing the facility which produced it, thus creating the name, the "China Lake grenade launcher".
All four remaining original China Lake Model grenade launchers are on display in museums. One, serial number four, is at the UDT/ SEAL Museum in Fort Pierce, Florida while serial number 13, is found in the War Remnants Museum (Ho Chi Minh City) in Vietnam., Serial number two is stored at the US Navy Museum in Washington DC. One additional launcher is on limited display in highly restricted US Navy facilities at NSWC Crane.
An effort to produce an improved version of the weapon began in 1992 when Samuel "Dutch" Hillenburg, a firearms writer specializing in military weapons, teamed up with master machinist Brian Fauci. In 2003, they achieved a breakthrough and were able to convince fellow writer and firearms enthusiast Captain Monty Mendenhall to finance their research effort. By 2004, they had a functional prototype and had formed Trident Enterprises Ltd. to continue their work on the project.
In June 2007, a taping of an episode of the popular military technology program, Weaponology was filmed which announced that Trident had been approached by a US company seeking to license their intellectual property in exchange for a royalty on each weapon produced.
In October 2009, the US company had cancelled its contract to manufacture any variation of the launchers.