Okay, I am fairly new too mags, and I am not to techy, but I had an idea for a closed bolt mag. My idea was that you could use an air powered ram (not sure what the tech term is) that is using air from the reg to close the bolt. When the marker is gassed up, the air that enters the air chamber would also push the ram forward, moving the bolt into the barrel. then, when the marker was fired, the air chamber and ram would be emptied of air, and the bolt spring would push the bolt back, feeding another ball into the barrel. Then, air fills the chamber and ram, pushing the bolt forward.
I am not sure if this would work, so any opinion and advice would be accepted. I have looked at Punishers PneuMag, which is partly why my mind started thinking about this, though I thought that if the three way wasn't needed, it would be more stable performance and maintance wise. Thanks IB.