I don’t by any means know all the details behind the construction of this paintball sentry gun, nor do I know exactly you’d make you own paintball sentry gun. However, if you want to see a demonstration of an awesome paintball sentry gun, then this is the place. If I could, I’d pay this guy to make me an autonomous paintball gun like this. See the video below:

Remember that paintballing (is that even a word?) can be very dangerous without safety equipment. The guy on the video gets shot at several times. If a paintball from the sentry gun were to have landed directly on his eyes, and he were not wearing the safety helmet he could have easily been blinded.