Airsoft Gases Tech Info

[garry]

Thought this might be interesting to start up and anyone welcome to add to it.

Similar things have been done before I suspect, but the gases also seem to change with changing regulations.

The temp / pressure relationships may give a guide on how you gun will / may perform.

 

The temp / pressure relationships I've given below, are at 24c. Two reasons for this. One is that 24c would be deemed a reasonably warm day in the UK, and secondly, this temp related to the only info I could find on "Black gas". I was getting intrigued as to what Guarder may be using as the composition. More on that later...

 

R134a (HFC-134a)

 

@ 24c = 79 psi

 

Green / Propane (R290)

(As it's generally accepted that green is simply propane with added lube) - in fact I think it was actually analysed professionally and this was the conclusion.

 

@ 24c = 120 psi

 

144a

 

(Seemingly Abbey's own designation)

I originally thought this was R600a, but the temp / pressure relationship does not stack up. It is said to have the same temp / pressure relationship as R134a. I strongly suspect from what I've found that it's an isobutane / propane mix (as R600a), but with the propane % increased to match the temp / pressure curve of R134a which it replaces.

 

@ 24c = Circa 79 psi

 

R744 (C02)

 

@ 24c = 890 psi

 

Mapp

 

The original Mapp began being phased out in 2007 and is often now found as "Mapp Pro". The original was mainly methyl acetylene. It is now mainly composed of Propylene. It's worth noting that this is more explosive in air (ignites more easily) than propane, and will burn with a higher temperature. Therefore, more caution may be required in it's use.

 

@ 24c = 150 psi

 

Guarder "Black Gas"

 

I'm picking on this as I've heard it really is quite powerful. So, what's in it?

This is difficult, as like other manufacturers, they don't like to give away the formula - and no msds seems available!!

On the can it says..CH2FCF3CH3 - there is no such compound as this and seems made up.

 

CH2FCF3 (on it's own) is actually R-134a, but CH3 seems a general term for a methane derived compound, such as Ethane for example. I doubt very much that this is R-134a with Ethane added to increase the pressure (although is it possible if a stable compound is the result). Ethane can develop dangerously high pressures should it not mix entirely with the R-134a to form a stable compound and boil off at a different rate (I'd need to confirm this) - and the standard aerosol cans would become a potential bomb.

 

The manufacturers "claim" a pressure of 16kg/cm2 @ 24c = 227 psi

 

My gut feeling is that "Black Gas" is actually R410a.

It's a close match, as @ 24c = 219 psi

 

This being the case, I'd like to hope that the aerosol cans that are used for the black gas, are more substantial than the others. Left in direct sunlight etc, this will develop seriously high pressures and could be dangerous. I'd also suspect it may do the mag seals no favours?

 

 

 

 

 

 

[Guges Mk3]

The "new" gas on the block is a Isobutane derivative.