Mk 18 Mod 0 grenade launcher
The Mk 18 Mod 0 was a 40x46mm grenade launcher used by the United States Navy during the Vietnam War and also the last known hand crank operated firearm since the Gatling gun.It was replaced by the Mk 19 grenade launcher in service with the United States Armed Forces.The use of a split breech mechanism allowed the weapon to be light and simple.The Mark 18 was used primarily on small boats or in fixed positions such as bunkers; their primary users were the so-called "river rats" and the SEALs.[citation needed] Armored Troop Carrier (LCM)s of the Mobile Riverine Force usually mounted two Mk 18s.
War Remnants MuseumHo Chi Minh CityGrenade launcherUnited StatesUnited States NavyVietnam WarHoneywell Corporation and Aeronautical Products DivisionCartridge40 x 46 mm grenadeCaliberActionRate of fireIron sightsPatrol Craft Fasthand crankGatling gunMk 19 grenade launcherUnited States Armed ForcespintleArmored Troop Carrier (LCM)sMobile Riverine Forcepublic domain