T148E1 grenade launcher

The T148E1 grenade launcher is a semi-automatic grenade launcher manufactured by Springfield Armory. It fires 40 mm grenades from a three-round magazine in a harmonica gun type configuration.

The weapon was tested during the Vietnam War. Though desirable for having a rapid way to reload a grenade launcher with multiple types of rounds available to the grenadier, the weapon was rejected for adoption due to being of flimsy construction, too awkward to handle and prone to jamming as well as the action of the weapon being too open and vulnerable to dirt.

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