Complete line of M203 paintball grenades and launchers Introducing the latest and greatest paintball grenades and launchers to the world of scenario paintball. Here you will find information on the paintball grenade launchers and videos of the RIS M203 grenade launcher, M203 Thunder Grenade(TM), and other paintball grenade launchers. The RIS launchers easily mount on any marker that will accept a rail system. Add a launcher to your arsenal today, end your games with a bang!