No need to apologize, it wasn't a personal attack on you, just a general statement about why it's good to at least expand on new ideas before shutting them down for "political reasons".
Anyhow, if it WERE plausible at this point, there could still be a functioning prototype system that looked nothing like a gun, that could show it worked...
It's also valid for you to bring up the point that implementing and demonstrating the concept could be cause for bad publicity, because you're not trying to shut this thread down and close our brains. Just keeping things on track, yea? So ... it's cool! (Not that you need my approval)
Oh, also - so, can someone confirm this? :
I was under the impression that the C3 fired by having the combustion move a piston and compress air, and that it wasn't actually the exhaust gasses firing the projectile. Now, I see that interesting animated GIF file, which indicates a totally different mechanism.
Which one is it? And what about building a combustion system which uses the combustion in lieu of a spring to move a piston head.
Or... How about magnets? I love magnets...