Check on 37mm.com There's a guy there named Grog that has a lot of info on flare launchers, reviews and has a couple instructional DVD's on building your own projectiles. I have a stand alone launcher (Cobray clone, made by EtCetera llc.) that works great, and can launch home-brewed flares/star-clusters/smoke up to about 350M. As a civilian, I wouldn't hang one on an AR-15 since a flare launcher is NOT a gun so I wouldn't want it permanently "married" to a gun. Of course, the usual fireworks laws/fire risks apply.