portable pressure theory...

[Hawkeye]

You can use propane for airsoft. Every airsoft site shows you how to make an adapter to fill up with propane. Green Gas IS propane.

[jimmy101]

The SpudWiki page on propane has the pressure versus temperature info. for propane.

[rcman50166]

I would like to comment on the original topic. Basically the answer is yes, however it would not be a care free system, With dry ice you would need a pressure guage and be able to watch it as it approaches the maximum alotted pressure, then you would have to relieve it. You could solve that with a custom trip valve. A redundant system would be needed, perhaps a burst disk exaust port. So the final thought would be that such a dry ice gun would be expensive, complicated, somewhat dangerous, and scary as hell when the failsafe went off. But, in the end, the gun is doable in a practical manner.

[jimmy101]

I would like to comment on the original topic. Basically the answer is yes, however it would not be a care free system, With dry ice you would need a pressure guage and be able to watch it as it approaches the maximum alotted pressure, then you would have to relieve it. You could solve that with a custom trip valve. A redundant system would be needed, perhaps a burst disk exaust port. So the final thought would be that such a dry ice gun would be expensive, complicated, somewhat dangerous, and scary as hell when the failsafe went off. But, in the end, the gun is doable in a practical manner.

The OP has a "pressure releif valve (that lets the pressure only get to a certain level)"

Trying to do it manually while watching a pressure gauge would be suicide.

It wouldn't require a "custom trip valve". A generic safety pressure release, with a suitable pressure rating, would work fine. The pressure relief values used in hot water heaters springs to mind as being about right in terms of pop-off pressure and flow capability.

You would still need to worry about the pop-off freezing, the affect of the extreme cold on the strength of whatever the gun is made out of, etc.

[jackssmirkingrevenge]

propane as a propellant?

[youtube][/youtube]

yay!

[MrCrowley]

A mouse would've stopped after the first time it caught fire and posed some threat

[jimmy101]

propane as a propellant?

yay!

The moral is;
1. Don't use it if you are an idiot.
2. Don't use it if you are going to purposely try to light it.
3. Don't do it in a semi- or full-auto.

But other than that it's a great idea.

[Jared Haehnel]

This has been another episode of entertaining videos by Jack... stayed tuned for Idiots on fire...