SpudFiles

Yes! A marble machine gun!!
All metal ofcourse!!

I bought a halon fire extinguisher at a flee market.
When I pushed that lever and saw the enormous cloud of gas coming out , I knew.
This thing could propell a marble machine gun.
A normal cloud or even vortex chamber would not work very well in my opinion because of the large dead volume.

In a cloud chamber the gas has to "punch" it's way through too many marbles to swirl them up.
This is no problem when u use bb's, but marbles are a bit heavier.

Anyway, it could be made easier for the stream of gas to lift those heavy marbles to the barrel port.
The idea is to get only one or two marbles at a time into the gas stream.

The diagram should explain my plan.
The shoulder stock holds the marbles, all neatly in a row,
waiting to enter the "cloud chamber".

The endcap of the mag, so to speak, is simply a ballvalve.
This would be best to reload quickly and seal properly.

The cloud chamber is 28 mm pipe, so the marble has some room to move around .The magazine is 22mm.

The mag is bent ( wich you can do with steel pipe)with one end pointing down towards the cloud chamber, the other end is,9 with the help of two elbows to get around the barrel,) connected to the ballvalve

The barrel should be .50" ( 1.25 cm?)
Maybe I'll add a rubber washer at the barrel entry to make the marble build up some pressure.

If I can finish this one in time I'll enter it in the competition.So don't copy this design yet.
I might add a CO2 bottle with regulator to keep the fire extinguisher up to pressure.Other thought would be to add a bottle to the ballvalve , filled with marbles to fill the reservoir very fast.

So the marbles have to flow through the 90o elbow? Not sure if they can do that.. then again I am a noob still.

i dont know if that will work because you would need to dump alot of air and have a huge air resovour to be able to to accomplish that cloud.

if your going to do that you might as well just have a gravity fed magazine right after the elbow with a tee and eliminate the little cloud chamber. you could also do a hopper this way.

I like that idea and if he is using a fire extinguisher (sp) you could make multiple shots from one fill.

This is a coinsidence last week i found a fire estinguisher and i attached a schrader valve to the tank, i have to go to the gas station two blocks away to fill it because my pump doesent reach 250 psi, well anyways what i do is screww off the top and fill it with water, anount 3/4 of the tank and then pressurise it. Its loads of fun. But i got bored to i attached the hose to a metal pipe and i turned it into a brech barrel and it fits marbes perfect and the first couple of shots will go through 1/2" ply like paper and then the power decrases, im sure that with time an automatic could be achieved, good idea please post pics.

i wanna fire extinquisher no one sells them at flea markets here the best bet to get your hands on one is to nick it from the side of a house but we don't do things like that around here...im all legit when coming to making things like this

Balls CAN flow through elbows.Especially concidering the marbles are 16 mm ( First I thought .50") And the inner pipe( and the elbow too) is 19.5mm.
A gravity-fed hopper is a possibility, but I wanted to use the mag and "cloud"chamber as a stock.
This way the barrel can be extended backwards ( bullpup).
This will give me the longest possible barrel without having it stick out too far.

As I stated earlier, when I saw that big cloud of gas coming out, I knew.It has enough flow.The cloud of gas was 3 meters long.
Compare that to a blowgun!!

I would be careful about the marbles getting jammed at the elbow but it should be fine and the worse that would happen is the air would just flow around 2 marbles if they got stuck at the elbow.

The worst thing that could happen would be shattering a marble inside the elbow.

But hey...that would make it a full auto shard-shooter...who cares!!.

I think it will work...At least I'm confident enough to go ahead and try it.

full auot shard shooter eh? hmm gives me a few ideas it would be like controlled shrapnel. i think you could pull it off post some pics when its finished.

i have been wanting to use a fire extingusher for a pneumatic cannon for a while too. how much does a new fire extingusher cost? i would get it at a flea market too but i have never seen one at the fleamarket closest to me.

I think they go for like 30 in wallmart, not the red ones though. I was lucky to find one fo freeeeeeeeeeee!

ok find one at your house,ther must be somewhere, now when your parents arnt home empty the fire extinquisher of its contents and when your parents come home say there was a fire and you had to put it out(make up where the fire was could be anywhere )and ask your parents for the bottle as something to hang in your room
im yet to try this so wish me luck 8)

you sly bastard,
1. its not going to work
2. you are prolly going to have to start a fire (like in a garbage can or something)
3. it doesn't take a whole fire extinguisher to put out a little fire

nice try tho, lol