This is cool as hell home-made project but scary that you can really injure and possibly kill someone with it. Without infrared camera, the laser beams will not be visible. Either way enjoy the video.
Just finished building my 40W(!!!) laser shotgun!!! The output of this laser is complete insanity, and is made up of 8 parallel 5W laser beams totaling to 40W. The parallel beams are manipulated with lenses, sort of like how a choke modifies the spread of a shotgun blast.
The massive diode array is powered by a huge lithium polymer battery pack (capable up dumping 250A) and the laser array is regulated by a whopping 24 LM317 drivers.