Would nitrogen give 1.4 % more fpe than air?

[Xplorer]

Nitrogen is faster than oxygen. And air contains both nitrogen and oxygen.

When I weigthed the expansion rate of oxygen and nitrogen in proportion to their share of the air content I got a combined expansionrate that was lower than for nitrogen alone.

I got the result that nitrogen would give 1.4 % more fpe than air.

Are my calculations corect or have I musunderstod something?

 

[acs]

Simple answer, No.

Whatever it gains on one front it loses being a larger molecule and passing thru orifices slower, among other things.

I use nitrogen only in all my pcp, and its more or less the same fps/fpe as hpa. Its cleanliness and lack of moisture contamination is what makes it attractive. Seems o-rings last forever with nitrogen ...

jmo

 

[Okie2]

Ask Georgia Airguns. I think he runs nitrogen & will probably have all the ansers!

 

[JamesD.]

If you want big gains it's Helium. 
Otherwise I would just use quality D or E quality HPA from a quality compressor like the Alkin or Bauer

 

[Enkey]

Hi

I don't understand gases, I only know that pure oxygen in a pcp is highly explosive. Be careful with your experiments. I think it has to do with traces of aluminum powder and oxygen

Regards 

Enkey 

 

[Motorhead]

A large component is the reality that atmospheric air has filled the barrel AHEAD of any projectile and must be pushed out of barrel by the advancing of said projectile.

While there maybe a slight gain, the effort and cost to take advantage of it is SO SMALL, hardly worth the effort unless you have FREE access to Nitrogen ?

 

[Xplorer]

I'm mostly interested in if I have done the calculations corectly. Since the same principle for calculation should work for other gas mixes.

 

[JimNM]

1.4% on 1000 fps is 14 fps

1.4% on 850 fps is 11.9 fps

That would easily get lost in the noise for most shooters.

 

[Georgia Airguns]

As far as Nitrogen in comparison to regular air, I would not know, I have been only using N2 for the last six years and I love it. I get a 6000 PSI chest high one foot diameter welding tank delivered and the old one taken away for $60.oo. I don't have to deal with the noise, filters, electricity maintenance and cost of a compressor. 

N2 is clean, dry and ready to go. I put a $240.oo fill whip on it and it last a long time. Considering I use it almost everyday and a lot of times I am filling guns from empty. If you can get it at a reasonable price I highly recommend it.

Thanks

Charlie Frear, Georgia Airguns

 

[ackuric]

Nitrogen is faster than oxygen. And air contains both nitrogen and oxygen.

When I weigthed the expansion rate of oxygen and nitrogen in proportion to their share of the air content I got a combined expansionrate that was lower than for nitrogen alone.

I got the result that nitrogen would give 1.4 % more fpe than air.

Are my calculations corect or have I musunderstod something?

I'm too lazy to run calculations right now, but your approximations are probably not far off. Those confusing 1.4% fpe for 1.4% fps are mistaken. For example 1.4% more fpe is the same as increasing my 60 fpe rifle to 60.84 fpe which would be 8~ fps...even less then when bargaining with 1.4% fps increase...



-Matt

 

[DougB]

Where are you finding 6000 psI. Nitrogen?

I'm only finding it at about 3000 psI. here in Los Angeles CA.

 

[Georgia Airguns]

My local welding supply. I don't think they will deliver to LA.

Thanks

Charlie

 

[Xplorer]

ackuric

Yes. I think 1.4 % more FPE would give about 0.65 % more FPS.