The US Army has successfully tested a 3D printed M203A1 grenade launcher for the first time. Designated as Rapid Additively Manufactured Ballistics Ordnance (RAMBO), every component of the M203A1 grenade launcher, except the springs and fasteners, was created using the latest 3D printing technology. The barrel and receiver were made of aluminum using direct metal laser sintering and The trigger and firing pin were printed in 4340 steel. Reportedly, the 3D weapon has been test fired 15 times at indoor and outdoor ranges, “with no signs of degradation”. The prototype’s components were completed in just 35 hours.

The M203A1 grenade launcher, which entered service with the US Army in 1969, is an older design that was fitted under the barrel of an M16 rifle or M4 carbine.