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Pneumatic Propane Power
Posted: Mon Apr 30, 2007 4:16 am
by chaos
So ive been thinking.......
propane for a pneumatic i have seen it on a couple of gun and was contemplating doing it with mine, because i dont have access to CO2 or HPA cylinder i was thinking of gas.
the fact is if i have a continues supply of pressure to my gun it could very well be semi auto, cheap and affordable and best of all portable.
any thoughts on this people?
Posted: Mon Apr 30, 2007 4:17 am
by jackssmirkingrevenge
yeah. keep away from naked flames
Posted: Mon Apr 30, 2007 4:23 am
by chaos
**eh its stainless man im sure it could withstand it**
if ya diddnt know already the propane would be over saturated (wont ignite) but man it would be kool to let off over a flame.
Posted: Mon Apr 30, 2007 4:27 am
by jackssmirkingrevenge
Yeah, but imagine firing it indoors and somehow managing to get an exact 4% mix with the air in the room... unlikely, but something to keep in mind
Posted: Mon Apr 30, 2007 4:40 am
by goose_man
That would be very bad for the environment. Hydrocarbons such as propane are worse greenhouse gases than CO2.
Posted: Mon Apr 30, 2007 4:59 am
by chaos
do i care of the environment?......
man jack a 4% mix, that would really suck aye. but i think i wont shoot inside with it connected to gas
Posted: Mon Apr 30, 2007 5:13 am
by jackssmirkingrevenge
chaos wrote:do i care of the environment?......
Let's face it, all this global warming malarkey will only become a serious issue after our generation will be dead, so let future generations worry about it hehe
Posted: Mon Apr 30, 2007 5:30 am
by mega_swordman
As for propane powered, I think it is a novel idea. It is so basic, yet so interesting that it will captivate the masses...maybe. As for global warming, oh well, we'll figure it out sometime; but until then, we should live life to the fullest...maybe :dontknow:
Posted: Mon Apr 30, 2007 5:35 am
by jackssmirkingrevenge
mega_swordman wrote:As for propane powered, I think it is a novel idea.
There's one that's been submitted for the
contest
Posted: Mon Apr 30, 2007 5:44 am
by spudthug
cant propane only go to like 85 psi without going liquid and screwing up ur gun?? plus if u fire it off and then u breath it in im sure it would add up..some kids died like last month becasue they were in a basement having a sleep over and someone left a propane torch on..it wasnt lit..
Posted: Mon Apr 30, 2007 6:04 am
by chaos
spudthug wrote:cant propane only go to like 85 psi without going liquid and screwing up ur gun??
hmm somehow no i don't think so... the attached table shows that it has pressure at various temperatures... the submitted contest PB longarm gun seems to use it fine.
Posted: Mon Apr 30, 2007 7:11 am
by mega_swordman
jackssmirkingrevenge wrote:
There's one that's been submitted for the
contest
Hmm, didn't see that. I know we had a discussion on said cannons, but I didn't see that anyone actually built one. Thanks Jack!
For Chaos, Spudthug is partially right. Compressing a gas (in our case, propane) in a closed container raises the temperature. However, an interesting point I also read is the fact that propane, when over 100C remains in a gaseous form. So, whether you achieve enough pressure to raise the temperature can only be tested.
I have here the source of my information:
Compressing a gas does affect its temperature, it actually INCREASES it, which is exactly the opposite of what you need if you are trying to liquify it. However, as I said before, providing the gas remains below its "critical temperature" (and each gas has its own) at some point the increased pressure will cause it to liquify.
In the case of propane this temperature is 97 degrees centigrade. This is obviously just below the "normal" boiling point of water (100 C). If propane has a temp of 100C it is impossible for it to be liquified no matter how much pressure you exert on it.
In the case of Oxygen, it has to be below MINUS 118.57 C (155 kelvin) to be a liquid.
In Gnomon's case, and he is quite right, of bottled gas and the "it is partially liquid: you can hear it sloshing around", applies only in what you might term "normal circumstances".
If Gnomon's gas bottle (let's assume it contains PROPANE) is submersed in a large tank of boiling water, the bottle and propane (liquid and gas) will start to rise in temperature. As the temperature rises more of the liquid turns to gas, but more gas in the closed bottle means higher pressure trying to stop the liquid becoming a gas. However the evaporating liquid slowly wins the battle. At some point the bottle and propane will reach 100 deg. C. When this happens there will be no liquid propane in the bottle, for although it will be under immense pressure, it will all have turned to gas. Infact if the gas bottle is not strong enough it will explode.
As well as the
URL to this discussion.
I hope this cleared it up.
Posted: Mon Apr 30, 2007 8:33 am
by goose_man
Just got an idea...imagine a really, really, really small turbine engine (like a smaller version of the ones used in airplanes) hooked up to propane and attached to a bbmg as the air source. Though not feasible, it sounds pretty cool.
-goose_man
Posted: Mon Apr 30, 2007 9:07 am
by judgment_arms
Why not just run the BBMG off propane? And well you’re at it put a pilot light at the muzzle. It would be like a flame thrower, except flaming, molten airsoft BBs instead of napalm…
Yeah, propane would be nice source of power for pneumatics, green gas airsoft guns use propane, and they’re more potent then Co2 guns.
I, personally, wouldn’t use it; I’d end up blowing something up or setting something on fire…
“No officer, it’s not supposed to be a flamethrower…”
Posted: Mon Apr 30, 2007 9:56 am
by chaos
“No officer, it’s not supposed to be a flamethrower…” lol *add to comment* "its supposed to be a homemade airgun"
lol either way ill get dun for it stupid aus gun laws.....
still i dont see the reason not to use this stuff , oh and if it does liquefy wouldn't it turn straight back to gas after the valve opens?