Over on hackaday I found a pointer to a home built airsoft minigun modeled after the GE M134. Jakub Kiryllo wanted a minigun replica but was put off by the multi-thousand dollar pricetag. So he designed his own, each piece machined out of aluminum on a CNC machine. It only looks like a minigun, the barrels don’t rotate and the gun actually only fires from a central barrel.
Underneath the cosmetic facade, however is an airsoft gun that fires an amazing 3000 rounds per minute. (See the youtube video) The box in the picture is the ammo pack, which holds 16,000 BBs. It uses air pressure and solenoid valves to deliver the needed feed rate to the gun. Assembly details for the gun and ammo pack are sketchy on the WWW page, but Kiryllo has available a complete set of 3D models for every part in the gun created in Solidworks. I guess if you have Solidworks, and a CNC machine, and plenty of aluminum stock lying around, and are really into airsoft, you can probably figure out the assembly.
For those who aren’t enthusiasts, airsoft guns shoot 6mm or 8mm plastic BBs. In comparison to a traditional BB gun, airsoft guns have a much lower muzzle velocity, much lighter BB mass, and are generally considered “safe”. They are used in shooting games similar to paintball, training exercises, etc.
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