All you've done if I understood it correctly is added a flow restriction which isn't really going to help performance. Granted, it will increase gas velocity, but reduce the rate of pressure increase in the barrel.

The 40mm round has a "burst disk" which generates high pressure in the cartridge ...

Very nice clean design, I think it has a really cool futuristic vibe to it.

Not to be a stickler, and I'm not sure why anyone didn't mention this, but... did you check with the mods about the flameshooting video, to make sure it's kosher? I don't wanna be a pain, just thought I'd ask.

So, the big question is, since "It was built to test the failure of ABS DWV non pressure rated pipe"... when are you going to blow it up?

Don't be ashamed of the comments, there's nothing wrong with starting with a ball valve... and a spring loaded one is just as cool.

And don't think some of us didn't notice the killer pinstriping on all your stuff there... please tell me you did those yourself, being a fellow welder/car guy ...

That's pretty good, even though I'm only Dutch by descent. Reminds me of a good friend who programs automation for a living.

Now, to see the OTHER side of the coin regarding a welding robot, go find the music video for "Believe" by the Chemical Brothers.

That thing has quite a bit of power for an air gun, what kind of pressure/caliber is he using?

I just think it's great that all your neighbors came over to admire it, and not to threaten calling the cops on you.

By the looks of it, is this going to be used for scenario paintball? If that's the case, do you have plans to add a CO2 setup at some point?

I agree that the chamber makes a nice shoulder stock, but for portability, I would suggest perhaps taking down the barrel a little bit. Most of the nerf ...

I stumbled across this site the other day and thought it might be of some use to the members here, so I thought that I'd post it. It has animations of almost all of the major air-powered paintball markers on the market, including some older, obsolete ones, and even Tippmann's propane powered, pump ...

Marpat, where are you from? I'm from the midwest, a rural area at that, and I'd be really surprised if most of the people I knew in high school hadn't used a firearm or known how to jump start a car (the guys anyways, no offense to any ladies here). I think it's part of the culture more than ...

The simple, short answer to your question is, as it has been already said:

Either let it out somewhere that you don't think anyone will catch you, or bite the bullet and pay 50 bucks to get it done professionally. Those are really your only 2 choices.

Surprisingly, one important thing here has ...

Rustoleum is like primer and paint in the same can, so you can apply it right on the metal.

Also keep in mind the age old rule... the key is not in the paint, but in the prep. Get rid of any rust or crud with a wire brush or wheel, or some sandpaper. Then use some kind of lint free cloth or paper ...

I saw Biged's MA1A bazooka just the other day. I agree, it's a very nice piece of work. I had no idea that he used a toolies, I just saw that he piloted it with a QEV. I'll have to keep that in mind.

Ali, I don't mind a coax, but I really don't want to have to remove the piston to get a nerf in ...

That's a beautiful piece you got there, top notch work. Your welds look pretty nice too... I gotta comment on those, I weld for a living. I wish I could make a nice steel cannon like this but I'm just afraid it'd be topo darn heavy. How much does yours weigh?

The hop-up is interesting, it's alot ...

I dont know if this works as well with finished wood, but I do know an old technique for drilling thru a painted panel on a car, without chipping the paint; put a couple pieces of heavy masking tap down, to keep the surface from marring or flaking around the hole.