Already suggested this idea, ya gotta remember that Ball Valves have a smaller inner diameter as well. The idea works, it's just not useful.

You'd think the average person would let go after hitting the beach the first time. How come the common sensed people always end up dead or more injured from accidents while the idiots usually just brush it off?

Bushings are the same outer diamter as the pipe, so they fit in pipe sockets, such as couplers or other bushings. Most stores have 3" to 2" bushings, and 2 to 1.5" bushing, add a 3" coupler and you're set.

If it were trigered as soon as someone stepped on it wouldnt it fire while the user only had 1 leg on it? That could really screw someones leg up. Unless they're jumping with both feet on it. Would it work if the cylinders were precharged and there was a latch holding them down? Just latch it down a...

I used a simple long nose lighter for my cannon, the trigger mechanism is cool for a bazooka style handle, plus they're only like 3 bucks. I made a simple combustion for under $15 since Home Depot sells those 2 foot sections and small diameter pipe is cheaper. 350 Yards seems a little far, that dist...

It looks like it can only load vertically...you'd need a tube and pin to press the ammo in if you want to load for any other direction. Not sure what makes this bullpup either.

14 bucks for 5000 BB's is pretty much the average price. Another kinda pointless ammo you could use are Qtips, they fit in my airsoft shotgun nicely, had to use it to fire sharpened Qtips at a foil balloon on my ceiling since BB's would just bounce off.

Modding Halo is easy and somewhat amusing, you can actually just mod the downloadable Trial version, look for a program called HMT 3.5, some slight intrusction is needed to get started though. You can make some medieval weapons such as Ballista and such. Go-Karts, Treaded Go-Karts, RC mini sub, SCUB...

The only problem I've had was when I was buying some rubber tubing for a pop dispenser for my dorm room, the guy asked me if I was making a beer bong, which is reasonable considering it's Kalamazoo, home city of Wastern Mich Unv. I had an interesting conversation with him about it, he said he's had ...

Ah didn't notice it in the corner in tiny front combined with red/green colorblindness, way to look out for the viewer. Try cutting open a can of Sterno, lighting that and shooting it, I wonder if you'll get a more "jet" like flame following the projectile. You should add a scope and use it for Nerf...

Nice clean cannon, I haven't seen a coaxial thats filled from the chamber side before. So what's with the video anyways, 1:10 of you lighting something on fire, then 2 minutes of slow motion burning......what did you even shoot at?

Basically. Any elastic tubing should work, I just might have access to some free bike innertubes soon from a scrapped bike. I'll prolly use a bunjee corded bike pump so I can basically cock the gun once for multiple shots.

Well I figured the innertube would compress the air in the chamber as shrinking the volume therefor keeping the pressure the same, like a balloon just with a PVC cage to keep it from popping.

I'm using a sprinkler valve, I plan on having a main chamber before the valve that gets refilled by the innertube chamber with a very small inlet between the two chambers to keep the valve from dumping the innertube chamber. I left some stuff out sorry.

The basic idea I have is to have an innertube as my chamber housed inside a PVC tank, I'm wondering how much the elasticity of the innertube would keep the pressure near. I basically need constant pressure for multiple shots. It's either that or adding some elastic to a bike pump and letting that st...