[KRA SHARPSHOOTER]

Lord Odin asked me to do a simple test comparing CO2 vs. HPA. I had nothing better to do this evening so I decided to attempt this test right away.

Basically this test consisted of simply shooting 50 shots through my A-5 with CO2, then switching to HPA and shoot another 50 shots.

Tanks:
I used a 9oz CO2 that was full minus 6 shots from chrono, and about 60 shots from testing out my TUSK yesterday.
The HPA tank that I used was a Pure Energy 72ci/3,000psi. It was filled to 2,500psi before I conducted this test.

A-5 Specs:
Tippmann A-5 *Polished Internals*
Dogleg Air Thru Stock
12″ C-Series Barrel
Response Trigger *shooting semi*
Hogs Den TUSK Trigger
TechT Complete Cyclone Upgrade Kit:
= Vortex Mod
= Lightning Rod
= QEPH
= Squishy Paddles *Green*
Remote line.
Lubed with Hoppes #9 oil.

Testing Data:
CO2 vs HPA - Google Docs

My opinion:
I'll keep this simple. It seems as though HPA is much more consistent over CO2.

[velocity1221]

Yeah thats pretty cool, wish i had a chrono to check this out on. But the jumps in co2 velocity are huge compared to hpa's.

[GrenadeMaster]

So you have proven it to be true that hpa is more consistent on an a-5. I would agree to that.

I do however think that it is VERY gun depedent.

For example my phantom is +-3 on c02 on a bad day... I have gotten +-1 at times. (I chrono and 3 shots read the exact same fps). On hpa I get +-10 on bad days. I will do a test replicating yours with my phantom tomorrow to see if this is true... but experience tells me it is.

---------------------------------

And I am moving this OUT of the experiment vault... doesn't belong here yet. Bryce or CockerPunk, lemme know if I am wrong to move this.

This post has been edited by GrenadeMaster: 08 April 2009 - 09:46 PM

[Lord Odin]

I think this is a great test because it puts one of our most common beliefs that we take for granted to the test and backs it up. Awesome job, KRA.

[Dr. Isotope]

HPA is more consistent because it starts as a gas in the cylinder and stays a gas in the gun.
CO2 can be inconsistent because it starts as a liquid in the cylinder and becomes a gas in the gun.

As an average, HPA will net ~10 shots per cubic inch from a 3000psi tank.
As an average, CO2 will net ~50 shots per ounce of tank size.

So a 48/3000 could be expected to net ~450 shots.
A 9oz CO2 tank would net ~450 shots.
But a 20oz CO2 tank, which is physically similar in size and weight to a 48/3000, would net ~900 shots.

CO2 is not an all evil thing. Many people still use it to great effect. High-pressure guns, like Phantoms and many Palmer's guns, prefer CO2 because the inlet pressure is higher than what an HPA tank reg will provide.

[cockerpunk]

great performance from the a5 on that too. SD of 3.5 is pretty damn good.

good test!

[D.K.]

Nice. You could've further tested it between different climate conditions (where C02 would've FAILED). Haha.

[Texas Cheezburgr]

Cool.

[Christopher]

GrenadeMaster, on Apr 8 2009, 10:44 PM, said:

So you have proven it to be true that hpa is more consistent on an a-5. I would agree to that.

I do however think that it is VERY gun depedent.

For example my phantom is +-3 on c02 on a bad day... I have gotten +-1 at times. (I chrono and 3 shots read the exact same fps). On hpa I get +-10 on bad days. I will do a test replicating yours with my phantom tomorrow to see if this is true... but experience tells me it is.

I will also do a test with my Shocker. I have a feeling that we will see drastically different results once the CO2 is regulated. HPA had a pretty big advantage in this experiment.

[brycelarson]

GrenadeMaster, on Apr 8 2009, 09:44 PM, said:

So you have proven it to be true that hpa is more consistent on an a-5. I would agree to that.

I do however think that it is VERY gun depedent.

For example my phantom is +-3 on c02 on a bad day... I have gotten +-1 at times. (I chrono and 3 shots read the exact same fps). On hpa I get +-10 on bad days. I will do a test replicating yours with my phantom tomorrow to see if this is true... but experience tells me it is.

---------------------------------

And I am moving this OUT of the experiment vault... doesn't belong here yet. Bryce or CockerPunk, lemme know if I am wrong to move this.

that's prob because of the sweet spot of your gun against the output pressure of your HPA tank. with equal output the HPA is better.

[Christopher]

brycelarson, on Apr 13 2009, 08:30 AM, said:

that's prob because of the sweet spot of your gun against the output pressure of your HPA tank. with equal output the HPA is better.

Ok this might sound REALLY stupid, but I have a different theory. Remember when you guys did that preliminary tank regulator testing (I can't find it for some reason)? The consistency of the output pressures varied quite a bit. Is it possible that since the HPA is not being dual regulated, that the fluctuations are more noticable than than the fluctuations of the CO2 tank?

Just a thought.

[brycelarson]

Christopher, on Apr 13 2009, 10:51 AM, said:

brycelarson, on Apr 13 2009, 08:30 AM, said:

that's prob because of the sweet spot of your gun against the output pressure of your HPA tank. with equal output the HPA is better.

Ok this might sound REALLY stupid, but I have a different theory. Remember when you guys did that preliminary tank regulator testing (I can't find it for some reason)? The consistency of the output pressures varied quite a bit. Is it possible that since the HPA is not being dual regulated, that the fluctuations are more noticable than than the fluctuations of the CO2 tank?

Just a thought.

prob not - I've seen some tank regs go from 750-950, but CO2 can be from the high 500's up to 1200-ish. I've never seen a HPA tank fluctuate that much.

[Spitlebug]

GrenadeMaster, on Apr 8 2009, 07:44 PM, said:

So you have proven it to be true that hpa is more consistent on an a-5. I would agree to that.

I do however think that it is VERY gun depedent.

For example my phantom is +-3 on c02 on a bad day... I have gotten +-1 at times. (I chrono and 3 shots read the exact same fps). On hpa I get +-10 on bad days. I will do a test replicating yours with my phantom tomorrow to see if this is true... but experience tells me it is.

---------------------------------

And I am moving this OUT of the experiment vault... doesn't belong here yet. Bryce or CockerPunk, lemme know if I am wrong to move this.

I would love to see you prove that you get (+/-) 1 fps. In fact, head over to the Paintball ASTM thread and download the Kuhnley-Gansner Standard Consistency Test (KGSCT) and do the testing. I think you will find that your marker will have a hard time beating (+/-) 4 fps tops.

Here is the BETA (KGSCT):
http://www.sicandbryce.com/paintball/Paint...ng+Document.xls

[Christopher]

brycelarson, on Apr 13 2009, 12:16 PM, said:

prob not - I've seen some tank regs go from 750-950, but CO2 can be from the high 500's up to 1200-ish. I've never seen a HPA tank fluctuate that much.

While CO2 can fluctuate from 500-1200, it won't unless the temperature of the tank changes. If you are not causing significant cooldown inside the tank, you won't get any fluctuations. It's the same principle that allows siphon setups to run so consistently.

I don't really know a whole lot about the direct impact of pressure vs. velocity. But could you really expect good consistency out of a 200 PSI variance, regardless of the gas type? Something about that just seems off. I don't see how sweet spotting the pressure could negate that large of a pressure change.

[Spitlebug]

Christopher, on Apr 13 2009, 09:52 AM, said:

Something about that just seems off. I don't see how sweet spotting the pressure could negate that large of a pressure change.

It can't.

[Timmy]

Dr. Isotope, on Apr 8 2009, 10:02 PM, said:

HPA is more consistent because it starts as a gas in the cylinder and stays a gas in the gun.
CO2 can be inconsistent because it starts as a liquid in the cylinder and becomes a gas in the gun.

Saying this isn't proving it is true.

[Christopher]

Timmy, on Apr 13 2009, 07:43 PM, said:

Dr. Isotope, on Apr 8 2009, 10:02 PM, said:

HPA is more consistent because it starts as a gas in the cylinder and stays a gas in the gun.
CO2 can be inconsistent because it starts as a liquid in the cylinder and becomes a gas in the gun.

Saying this isn't proving it is true.

And it's actually wrong. HPA is consistent because it's regulated. If it wasn't regulated, it would be MUCH less consistent than CO2, because the output pressure would constantly be going down.

Just look at airguns instead of paintball guns. Some airguns use unregulated HPA, at about 3000 PSI. Each shot is drastically less powerful than the last. Airguns powered by CO2 are much more consistent. There's nothing magical about it.

[Lotus]

Sweet spotting the reg helps mitigate pressure changes because as the pressure drops, the velocity drops, and as the pressure increases, the velocity drops. Therefore, you don't get drastic changes in velocity even when you get changes in temperature. This occurs because of the increased pressure forcing the poppet valve closed thus lowering the mechanical dwell.

(for demonstration purposes only)
For instance, a non sweet spotted could have a velocity of:
289, 290, 290, 291, 291, 291, 292, 292, 293

and sweet spotted, that would be
289, 290, 290, 291, 291, 291, 290, 290, 289

As you can see, there is a drastic difference in consistency even though the degree of pressure variation is the same.

[Starter]

Christopher, on Apr 13 2009, 08:01 PM, said:

Timmy, on Apr 13 2009, 07:43 PM, said:

Dr. Isotope, on Apr 8 2009, 10:02 PM, said:

HPA is more consistent because it starts as a gas in the cylinder and stays a gas in the gun.
CO2 can be inconsistent because it starts as a liquid in the cylinder and becomes a gas in the gun.

Saying this isn't proving it is true.

And it's actually wrong. HPA is consistent because it's regulated. If it wasn't regulated, it would be MUCH less consistent than CO2, because the output pressure would constantly be going down.

Just look at airguns instead of paintball guns. Some airguns use unregulated HPA, at about 3000 PSI. Each shot is drastically less powerful than the last. Airguns powered by CO2 are much more consistent. There's nothing magical about it.

tnat is why hpa is more money because it is REGULATED so its going to outperform c02 in most cases

[anthoneyk123]

im saying this right now propane is more efficiant than all