That's very interesting, and something I like the sound of. I just wonder if you could get the hardware to act consistently.

So now I know that messin' with the emitter is not cool by ... what? ... Danville Standard U.S. Rules of Engagement? I'm cool with that and it saves me work. I'll just make the tube for 9mm from the tip of the unmodified emitter. I still might play around with them (if I can find time, which is doubtful) just for curiosity.

So what about the number thing? Mine are 890NM radial. Anybody care to educate me on that? I think I heard stock Tamiya is 920NM?

And does anyone think there's a difference between brass and aluminum tubing? Or plastic? Would polishing the inside of the tube help? These are the kinds of things I mean when I say I want the tank to be as good as I can make it. Does anyone think I'm getting off topic? Should I start a different thread?