portable pressure theory...

[Ragnarok]

For some reason I thought of Captain Obvious...

I was considering quoting Schwarzenegger in Last Action Hero: "Look, Elephant!" - but that was a little too obscure.

[Jared Haehnel]

The concept of using dry Ice as a source is not new people have brought it up before. Your right it would make it easier as you wouldn't have to have a air compressor or electricity.

But I would think that if you didn't do it right the incredibly high PSI and cold gas could cause a huge liability if something went wrong. Don't get me wrong spudders have done it before and gotten great results.

How ever I would encourage using something that can be stored at a lower PSI and try adjusting the amount of volume or use a different gas such as helium which has a higher SOS.

[bigbob12345]

I do this and have mentioned it many times before.
What I do is I have a burst disk made to burst at a said pressure and I put the dry ice in the chamber clamp the burst disk in the union and wait for it to burst.
The problem with it is that if you want it to burst quikly you have to put a lot of dry ice in but that will waste some as it all goes flying out the barrel when it fires but if you put just enough in to make it burst it will take a long time somtimes even 20 or 30min and dry isnt cheap to the average person.
I get it for and that is why i use it.

[Jared Haehnel]

Perhaps stick one end of the chamber in nice hot water to speed things up a bit or use a propane torch...

[coolhippy80]

i just wanted a poetable scource of an efficient gas... would propane work? (here in aus i cant get regular co2 you see...)

[Hubb]

Propane will work for a portable pneumatic air source. There have been several topics posted that may be able to answer any questions you have about it also.

[MrCrowley]

i just wanted a poetable scource of an efficient gas... would propane work? (here in aus i cant get regular co2 you see...)

Yeah you can, you're just not looking hard enough

But really, you can. Though getting CO2 might be harder.

And yeah, you could use propane. Depending on the temperature the pressure changes, so on a hot Aussie day, it could get up to 150psi if I recall correctly.

[jackssmirkingrevenge]

would propane work?

yes

[Eddbot]

OH NOO!! the S400 pics are missing...

[Carlman]

and he talks about it here

and yea eddbot i noticed he deleted his photobucket account right after he left here , hes still got the youtube vids though

[ghostman01]

omg you serious Mr crowly i got that the other day to read and we also watched the movie twice lol

[squarles2007]

your going to use propane to power a pneumatic gun? hope nobody is a smoker in australia cause you would be shooting a large amount of explosive gas into the air. <Headline> Aussie Killed In Propane Mushroom Cloud <Headline>

just make a combustion gun no need for fancy valves and compressors and they sound way cooler (swoooosh vs. KAPOWWWWWwwwwww)

[rp181]

the propane wouldn't light, its moving way too fast, with insufficiant oxygen. On top of that, why would you be smoking in front of a gun?

[bigbob12345]

and they sound way cooler (swoooosh vs. KAPOWWWWWwwwwww)

you have obviously never used anything but a ball valve because a piston valved pnuematic charged with an anywhere near decent pressure will easaly double the noise created by an aerosol combustion. And it will have a nice big Booom that sounds much "cooler" than any combustion.

And about the propane igniteing in the air, it wont. It would dissapate to quikley in the air to have any possible way of igniting unless of course you purposly tryed.

[squarles2007]

I will agree that the chance of an explosion is slight but at some point as the propane dissipates it will go through its combustive limits and could ignite. also not all the propane will come out of the chamber so lets say your reloading the gun a.k.a. standing in front of it right as the propane is reaching is combustive limits from what's left in the chamber. all it takes is one spark like a static charge to ignite a fireball right at you. Murphy's law anything that can go wrong will. There is also the chance of a leak somewhere creating a cloud of gas around the gun, while this is a possibility in any style of gun using propane. I wouldn't do it because i don't like the idea flammable gases being used this way, ever seen a burn victim, i have its not something you want to have happen to anyone, and isn't everyone on this forum always saying don't do that, it will end up on the news and give bad publicty for spudguns. and if your going to go through the trouble of piping propane into it you might as well make a combustion, as for them sounding way cooler i was just being a smartass I didn't mean to offend any pneumatic fanatics and i'm sorry. oh and i never used aerosol combustion, metered propane injection. i'm not that much of a noob.

in final i wouldn't do it just because of the many different ways it could go bad