Check out this monster of a NERF gun, it is a beast of a gun. Peter Sripol modded a NERF Elite 2.0 Turbine CS-18 to be powered by a mini four-stroke engine mounted on the gun. The engine comes with half a horsepower. That is a brilliant idea for a Nerf Gun!
Check out the NERF gun in action in the video below. This thing shoots NERF rounds like a real machine gun! It’s awesome! It’s not quiet though, you can’t really come creeping up on someone with this firing on all cylinders.