"We Need More Firepower!"- Build a life-sized gun from WWI-Present (2013). You can build any type of gun you want, but it has to be an actual gun. NOTE: Please provide a video showing the gun firing. You gun MUST be able to actually fire some kind of official LEGO piece.
Another rough choice for Round 4. Caleb's firing mechanism seemed to be a little bit more original than yours, but yours was just as effective. Your overall shaping was better, and you have won my vote! Congratulations!