Then the question would be whether or not the gov classifies a spudgun as a "weapon".

And the most beautiful part is: Fire extinguishers are so easy to come by! People leave them lying around everywhere!
(That was a bad joke. No stealing fire extinguishers, people)

Actually, I think I do have a few old tanks around, and this might be pretty useful. A couple questions:
Can you charge ...

I'm going to the hardware store tomorrow, and I'll definitely check those test-plugs out. I'm having a hard time picturing them, and how they'll work, but it's worth looking at them. I can always glue them in, too.
Thanks.

You guys aren't understanding.
I want to seal off the airflow at the begining on the junction, keeping the flow out of the cosmetic areas. Here's a quick paint sketch:
http://i80.photobucket.com/albums/j170/celystialbeen/DiagramD.jpg
The blue circle is the rubber superball, and that's the point ...

Howdy Spudfolks

X-Mas is fast approaching, and in order to justify my recent spud gun obsession, I've decide to build a couple of gift guns.

My little cousin is ten years old, and he's way into Lego Bionicles. One of the weapons that these little robot guys carry is called a Zamor Sphere Launcher ...

I don't have any concrete numbers for you, as I don't really get very technical about measuring performance after completing a cannon.
I just start blastin' stuff.
However, I can tell you that there will be a noticable difference if you trade the switch for a pilot valve.
I'd say I saw, roughly ...

I hate bbq ignitors. I've experienced nothing but misfire problems with them. (I'm sure it's ignitors fault and not mine! lol)
You should just upgrade. For a few more bucks, you can pick up a cheap 65,000 volt stun. I got mine on ebay for twenty dollars, and that included shipping. It arrived in two ...

LOL...
Maybe try to find a good golf cart armor.

What would you make the hatch out of?
Sheet metal would probably bend. I don't know if I would trust wood.
The rubber seal might make it a hassle to slide it back and forth.

Why not just have it swing out on a hinge, then close on a rubber gasket and lock with a tension latch thing.

How big a barrel do you think you'll need to shoot a rolled up T-shirt??

I would think an unmodified sprinkler valve would be fine to launch t-shirts. You just need to lob them into stands, not blast people with them.

Where are you planning on using this thing.
And what are you gonna use to ...

That's pretty interesting stuff. Do you know what it's actually manufactured to be used for? I'm curious what kinds of places might actually carry this stuff on hand...

Just keep in mind that CO2 comes outcold. I've heard that PVC gets brittle when it gets real cold.

You might consider using copper and steel for this one.

Please tell me you painted white pipe black for that chamber. Otherwise that's not a cannon.
That's a grenade.

Go gently, friend.
Wear kevlar.

Also, in the future, you might consider a longer barrel.

You are arming the inbred pig people and you are a traitor to humanity!!

Very nice sniper. Looks tough.
I notice that the barrel is a little bit bendy or crooked. Maybe you could sleeve or stiffen that up for increased accuracy.

If your chamber is venting out through the air gun, that means that ...

I would definitely solder the copper tubing. It's actually really easy to do, and propane torches are pretty safe as long as you're not playing recklessly with them. Basically they're just overgrown butane torch lighters.

Depending on the PSI rating of that QEV, you could probably hold a lot of ...