After being inspired by AnthongRedbeard's http://www.thingiverse.com/thing:14991 I went about designing my own Nerf mine. The mine consists of two components, the top part holds 6 Nerf projectiles in a revolver cylinder arrangement with a central guiding hole. The base consist of a central guide that has a hole positioned for a retaining pin. Surrounding the guide are six ejection rods. Elastic bands are used to store the energy required to propel the projectiles just over 3 metres. My cylinder stopped printing about 75% through the print run but worked anyway so I haven't bothered reprinting it.