A VS with two empty arms and two Gatlin guns are required for this trick. Attach both guns to each side of the VS and fire only one of the guns a couple times. Then, start firing the second gun. If done correctly, one of the guns will reload while the other is firing, causing the guns to never stop firing until you run out of ammo or manually reload. This works great against any Akrid Boss, especially the one in Mission 05.