Well JH45, I don't think that I've seen anything like it in my 54 years. That being said, I was truly impressed. How about a dc selenoid with a momentary contact switch to release the air? Thats the fastest way I can think of to dump all the air at once. If you want to try darts in your air gun how about wire nuts with drywall screws driven through the backs of them. Once in a while we will shoot them through half inch copper M tubbing or emt [like a blow gun] when we're bored on the job. Hope you don't mind the input..............Jim