I am in the motor sports (spec miata in Az region SCCA, NASA, Cal Club, and others) field and both own and sell GOPro cameras. they are the most badass sports cameras and can be mounted anywhere. they are quite small, though i imagine you would want something a bit more low profile to mount to a rail. they go for about $200 with a mounting kit and a badass shatterproof/ waterproof case that lets you use it underwater. there are stick type cameras for mountain biking and whatnot, but the images they capture are not as nice and i wouldn't trust them to take a bb to the lens area and still function. I have entertained the idea of mounting my GoPro to the right shoulder of my plate carrier as is should hen look out over the gun like a left handed shooter would see with sights and all. if executed properly, the video would look like a first person shooter demo. sick huh? well hit me up if you want to buy one of those cams; we have plenty instock and even carry the more expensive HD variant.