CO2 Regulated

[d3vnull]

I purchased a 90 gram to bulk co2 adapter from @Baker Airguns , a 1.5 inch Ninja bottle extender, and a Ninja 13/300 psi aluminum HPA tank with a v2 regulator set to 1100 p.s.i. for my Hammerli 850.

I had the HPA tank filled with 3.4 oz. of co2.

I took it out in the TX sun where it was 98 degrees in the shade. The internal pressure in the bottle read 1300 p.s.i.

I experienced no valve lock. I did not do any chrono readings, but there was no POI shift during the session.

 

[baranjhn]

I purchased a 90 gram to bulk co2 adapter from @Baker Airguns , a 1.5 inch Ninja bottle extender, and a Ninja 13/300 psi aluminum HPA tank with a v2 regulator set to 1100 p.s.i. for my Hammerli 850.

I had the HPA tank filled with 3.4 oz. of co2.

I took it out in the TX sun where it was 98 degrees in the shade. The internal pressure in the bottle read 1300 p.s.i.

I experienced no valve lock. I did not do any chrono readings, but there was no POI shift during the session.

I thought CO2 is a “self regulating” meaning that in temperatures over 70 degrees it has a psi of about 825 to 900.

Interesting

 

[d3vnull]

I thought CO2 is a “self regulating” meaning that in temperatures over 70 degrees it has a psi of about 825 to 900.

Interesting

Here is a great article and chart on CO2

http://www.warpig.com/paintball/technical/gasses/co2dynamics.shtml

http://www.warpig.com/paintball/technical/gasses/co2pv.gif

 

[elwoodblues]

Be very carefull of C02 pressures Co2 is a liquid and if the temp of the liquid gets to 88 degrees F it will turn all the liquid to Gas at once and will easily blow a 3000 psi safety,

 

[baranjhn]

Here is a great article and chart on CO2

http://www.warpig.com/paintball/technical/gasses/co2dynamics.shtml

http://www.warpig.com/paintball/technical/gasses/co2pv.gif

Very interesting article!

 

[nervoustrig]

Heating CO2 to elevate the pressure and then regulating it down is a perfectly good way to exploit its inherent behavior, provided of course it is done safely as was the case here (Ninja tanks are fitted with a 1.8k burst disk like a typical CO2 tank).

 

[maxtrouble]

Why regulate Co2 when it is already being regulated by the ambient temperature? What is the goal?

 

[d3vnull]

Why regulate Co2 when it is already being regulated by the ambient temperature? What is the goal?

To avoid valve lock on the Hammerli 850 in the TX heat

More consistent shot velocity

To be able to bulk fill

To have the option for HPA if wanted

 

[maxtrouble]

So valve lock can happen in high heat? But the gun bottle and supply tank are at the same temperature so how does a regulator stop valve lock? And this project is make the rifle shoot in high temps without valve lock? Why not shoot a PCP or springer? Is there some goal with this Co2 rifle that I do not see?

 

[d3vnull]

The bottle can go as high as it wants. The regulator will only feed 1100 psi to the rifle internally.

I don't have enough strength to even cock my HW30S (C5-C6 quadriplegic).

Why not CO2? Maybe because no one else has done it.

 

[crosman2016]

Be very carefull of C02 pressures Co2 is a liquid and if the temp of the liquid gets to 88 degrees F it will turn all the liquid to Gas at once and will easily blow a 3000 psi safety,

Whoa! I did not know that!

 

[nervoustrig]

Why regulate Co2 when it is already being regulated by the ambient temperature? What is the goal?

CO2 acts as a regulated pressure source only if the temperature is unchanging. It’s a bit like having a regulated PCP whose setpoint is different every time you pick it up.

In other words, CO2 acts like a bad regulator. How much it matters depends on the range of temperatures in which one expects to be shooting, and how much tolerance there is for POI shift. By adding a proper regulator, consistency is improved.

 

[d3vnull]

very carefull of C02 pressures Co2 is a liquid and if the temp of the liquid gets to 88 degrees F it will turn all the liquid to Gas at once and will easily blow a 3000 psi safety,

I don't believe this is accurate. Read the article and look at the CO2 chart I posted. It explains the working temperature of CO2 and where it becomes unstable.

 

[elwoodblues]

I have been in the compressed gas biz for over 45 years and I can assure you that at a liquid temp of 88 degrees All of the liquid in a co2 tank ANY size will in fact turn to gas all at once I have observed this on more than one occasion and the inverse is also true drop the head pressure below about 150 psi and said liquid will turn to dry ice

 

[elwoodblues]

By the way if you dont believe me maybe you should actually read what you posted for exapmle

This works pretty well between 0 and 80 degrees F as long as your bottle is filled to 100% or less of its rated fill. To get a more accurate estimate, use the CO2 diagram.

Once all the liquid is used up, there's only gas in the bottle, and then pressure drops pretty quickly. 88 degrees F is the critical point for CO2, where all the liquid sort of evaporates no matter what (kind of complicated). Any way, above 88 degrees, the pressure depends on bottle volume again, but this is not too important since bottles should never get this warm.

So it doesn't sort of evaporate it tries to turn to gas all at once and will easily blow a 3000 psi safety co2 in liquid form contains 8.74 cubic feet per pound of liquid at 70 degrees higher temps expand it even more

 

[d3vnull]

I understand that at 88 degrees it becomes transcritical. Which means it acts as both a liquid and a gas. The tank has a burst disc of 5k and a regulator burst disc of 1800.

If I quit posting to the forum you can assume my configuration failed.

 

[elwoodblues]

I just didn't want anyone to get hurt with guns in the sun and burst disc's are quite exciting when they go. Be safe and have fun.

 

[d3vnull]

just didn't want anyone to get hurt with guns in the sun and burst disc's are quite exciting when they go. Be safe and have fun.

Thanks and I appreciate your concerns. It certainly made me go back and check my thoughts.

I do know that pressure calculations on 90gr co2 are at around 9000 psi and 12gr, although thinner walled, are supposedly higher because of less volume of the vessel.

I sort of had to assume the Ninja bottle was at least 3x the 3000 fill pressure.

Edit: And the burst discs are the ones installed by Ninja. I did not change them