SpudFiles

I came up with this strange new idea for a marble gun.
Instead of propelling the marbles with pneumatic power, why not fire?
not an explosion, just a constant torch. Propane is fed into a relatively small chamber (1in) which is attached to the barrel. At the same time, nitrous is fed into the chamber as a slow leak(via screw valve), just enough to give the chamber enough oxygen for a continuous flame.
My idea is not to make it go BOOM!, but to make it go WHOOOOOOOOOOSH, thus propelling marbles that are fed into the barrel.
ps. the gun shall be all metal.

Nitrous oxide is a non flammable gas. It boosts the power and acts as a cooler for example on the compression stroke in an engine NOS breaks down into its 2 parts nitrogen and oxygen (36%oxygen by weight). It breaks down when it is at about 580F or more. I would suggest pumping in some air also, maybe via a compressor.

i think I could just blow in some air with a compressor before firing, and then it could keep itself going. However, i would have to do that every time i stopped firing..... Maybe i could just get a bottle of oxygen, and squirt a shot in before each time i fired.

how much do you think something like this would cost?
if its close to $100, its probly not going to work for me.

i if you could keep it going i dont think it would have enough power to shoot marbles more than two feet out of it.

hmmmmm yeah...........well if i got the fuel mixtures right......
I think it would work if I got the mixtures right

ok... you'll get flame temps on the order of 3000k, so 1/10th the density of air, so 2 kilograms of fuel and oxidizer are good for, essentialy, a 300 gallon air compressor tank @ 150 psi.
Personaly, I'd burn the fuel in air (for cost reasons), but whatever.

DR's experience with marble machineguns of the cloud type indicates that that'll last you a good while, maybe 20-30 seconds, by a rough estimation of numbers haparzardly pulled from my memory.

so, are you saying that i should just attach a portable compressed airtank, like the ones you use for paintball guns, intead on a NOS tank?
now that i think of it, that sounds like a better idea.....

Do any of you think this is a stupid/pointless/crazy/etc idea?

Correct me if I am wrong but won´t that thing will heat up fast. So if you do make it dont forget heat sheilding of some sort, or be prepared to go to the hospital

In response to ammosmoke, I think thats its a pretty good experimental gun, but I doubt you are going to get a lot of distance from it. If you've got the time and the money, I say go ahead and build it.

creative, but if you don't have much experience with guns similar in style to this, don't try it, yet. if you went ahead and built it right now you are bound to find numerous problems, probly with the fuel/air ratios. look over your design and think about it, just keep re-creating your design until you have a final product, then review it again, then build it.

-Flinch

Well, I now that I think of it, I probably don't have the money to spend on it........ And, I don't have much experience building guns like it. I would, like you said, have to make a lot of prototypes. BTW, if somebody wants to make a gun like this using my idea, GO AHEAD I DON'T CARE.

My only fear is complaining neighbors, and possibly an angry mother.

EDIT: This would be a good summer project I think, when I have more money, time, and could go somewhere and shoot it.