Not just a grenade launcher. Grenades, too.
“The U.S. Army 3D-Printed a Grenade Launcher and Called it R.A.M.B.O.”
The grenade launcher barrel and receiver took about 70 hours to print and then required 5 hours of post-print finishing. The barrel was tumbled in an abrasive rock bath and then Type III hard-coat anodized to provide a rugged finish.”
3D printed training grenade. Note plastic nose and aluminum sintered body.
U.S. Army Acquisition Support Center
The grenade launcher wasn’t the only thing the Army 3D printed. Tt made grenades, too. The Army printed several M781 training rounds, which do not have explosives, out of aluminum and glass-filled nylon. The 3D printed grenade launcher and grenades were tested in October 2016 and displayed zero degradation after 15 shots. 3D printed grenades came within five percent of the muzzle velocity of regular production grenades, proving that the system was performing close to the real thing.”
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