Nitrogen or Oxygen

[geoffwales]

Seems to be a bit contentious issue, but i have an empty bottle and its my 1st pcp whats the advantages and disadvantages of each when recharging a bottle to use with it

 

Cheers

 

Geoff

[silver pigeon69]

Can you use Oxygen in a pcp? to have oxygen put into a cylinder, the cylinder needs to be O2 cleaned and only filled with O2 or Clean air.

[Carman06]

No to oxygen. Risk of ignition when exposed to oils due to lowering flash point.

 

Although Nitrogen is more stable then breathing air it is generally considered to remove confusion only dry breathing air should be used.

Edited August 3, 2015 by Carman06

[robbiep]

NEVER, EVER fill with pure oxygen. The greases and lubricants used in your gun are flammable. In addition, your tank has not been prepared to 'O2 clean' standards, which means it is not suitable for high concentrations of oxygen.

 

Same for pure nitrogen. Imagine what happens if the valve fails and your tank vented while in the car, while you were driving along. Instant lack of oxygen, you suffocate in your seat in seconds.

 

To be honest, I'd be astonished if a dive shop would allow you to fill with anything other than air.

[rodp]

Absolutely no to Oxygen.

Pure Nitrogen is OK, used it for years. Not only is it a true inert gas it's not so susceptible to pressure changes with varying temperatures but as it contains no oxygen your rifle doesn't oxidise inside (rust). If you can get the use of a full size cylinder it lasts for years.

[Carman06]

Absolutely no to Oxygen.

Pure Nitrogen is OK, used it for years. Not only is it a true inert gas it's not so susceptible to pressure changes with varying temperatures but as it contains no oxygen your rifle doesn't oxidise inside (rust). If you can get the use of a full size cylinder it lasts for years.

+1

[DIVERD]

As said before, filling with oxygen is a disaster waiting to happen. The cylinder would probably fill ok if done slowly, but firing would expose the oxygen to heat and fuel, and it would eventually explode - no doubt about it. All the seals would corrode rapidly as would all the metal parts. it is a huge dont do it!

 

Nitrogen is way better, but to be honest little better then clean dry air, so unless you have access to loads of HP nitrogen then dont bother.

 

If messing with other gases in a PCP then helium will give considerable more power, and has none of the explosive issues oxygen has. I forget the figures, but when i tried this years ago the cronographed pellets were going way faster, i think a third faster but could be wrong. It would of course break 12ft/lb so would get you in a lot of trouble. You cannot breath pure helium - it would kill you, so leaks in confined spaces would be dangerous, and it is an incredibly leaky gas. Finally it is incredibly expensive.

 

They are made for air, air is cheap, air works

[Sha Bu Le]

Air guns can diesel if not maintained properly e.g. oil in barrel. If oxygen were used in a gun that was dieseling the shooter may well get a proper fright. May not affect the storage cylinder but if it had a slight leak !!!! the cylinder could become the equivalent of a pipe bomb.

 

NO OXYGEN EVER

[Mike737]

I wonder if the OP meant air, not oxygen? It's a common mistake made by people (even TV presenters!!!), to refer to scuba divers' air cylinders as oxygen tanks/cylinders...

 

Mike.

[swampyis1968]

+1

so you could use argon then as that is an inert gas as well ??

[kyska]

so you could use argon then as that is an inert gas as well ??

 

No, using anything other than air or carbon dioxide is illegal.

Edited August 4, 2015 by kyska

[Mentalmac]

Haha I never knew what was going in mine - just went to the dive shop and handed bottle and said "fill her up". They knew what I wanted.

[Underdog]

 

No, using anything other than air or carbon dioxide is illegal.

How come mate?

[Dekers]

 

No, using anything other than air or carbon dioxide is illegal.

 

 

How come mate?

 

Indeed, illegal?

 

I am not disputing, simply asking for clarification, not heard of that!

 

Cheers!

[robbiep]

Haha I never knew what was going in mine - just went to the dive shop and handed bottle and said "fill her up". They knew what I wanted.

 

Your cylinder says on it what it is to be filled with. "Breathing air"

 

SCUBA divers often use NITROX - also called 'enriched air', which has a higher percentage of oxygen than air does. This is so that, for shallower dives, you need less decompression time, or quite possibly no decompression time. However using NITROX does mean that your maximum diving depth is reduced, as the higher oxygen level means that it becomes toxic as you go deeper. "oxygen toxicity" is well-known in diving circles, and is as big a problem as nitrogen narcosis. The bends (decompression sickness) are, however far more common than either of those.

 

For a diver, for your tanks to be filled with NITROX they MUST be NITROX tested. A tank that is NITROX tested can be filled with air or NITROX. Common fills are 27%, 32% or 36% O2.

[kyska]

How come mate?

 

Hi,

 

If you use nitrogen or other gases other than air or Co2 the rifle becomes an illegal section 1 firearm. Co2 was section 1 until 1997.

 

"2.45 By virtue of section 48 of the 1997 Act, firearms using compressed carbon dioxide as the power source are treated as air weapons and, if not regarded as ‘specially dangerous’ (over 6 foot lbs in the case of a pistol or 12 foot lbs in the case of other air guns and air rifles) are thus exempt from the firearm certificate procedure. Firearms using other gases are not so exempt."

 

Obviously we know air is ok!

 

Some people always question the use of gas ram air rifles, so I'll get in there before someone does, gasrams don't use nitrogen as the propellant.

 

I should clarify, illegal, as in you'd need a FAC for an air rifle using other gases as a propellant, most are S5, such as dart guns for dangerous animals.

Edited August 4, 2015 by kyska

[Underdog]

Thanks for that quote, often wondered! :-)

[Bobba]

Your cylinder says on it what it is to be filled with. "Breathing air"

 

SCUBA divers often use NITROX - also called 'enriched air', which has a higher percentage of oxygen than air does. This is so that, for shallower dives, you need less decompression time, or quite possibly no decompression time. However using NITROX does mean that your maximum diving depth is reduced, as the higher oxygen level means that it becomes toxic as you go deeper. "oxygen toxicity" is well-known in diving circles, and is as big a problem as nitrogen narcosis. The bends (decompression sickness) are, however far more common than either of those.

 

For a diver, for your tanks to be filled with NITROX they MUST be NITROX tested. A tank that is NITROX tested can be filled with air or NITROX. Common fills are 27%, 32% or 36% O2.

I'm aware of dive cylinders requiring hydrostatic tests, visual tests and to be O2 cleaned. But a NITROX test is a new one on me. Please explain what this is. O2 cleaning is required for Partial Pressure blending when pure oxygen is pumped into the cylinder first before topping off with air but O2 cleaning is not a requirement for pre mixed Nitrox up to 40 %.

I would also welcome a reference to your evidence which suggests that the bends is far more common than Nitrogen Narcosis (the Narcs).

Thank you.

[Dekers]

 

Hi,

 

If you use nitrogen or other gases other than air or Co2 the rifle becomes an illegal section 1 firearm. Co2 was section 1 until 1997.

 

"2.45 By virtue of section 48 of the 1997 Act, firearms using compressed carbon dioxide as the power source are treated as air weapons and, if not regarded as ‘specially dangerous’ (over 6 foot lbs in the case of a pistol or 12 foot lbs in the case of other air guns and air rifles) are thus exempt from the firearm certificate procedure. Firearms using other gases are not so exempt."

 

Obviously we know air is ok!

 

Some people always question the use of gas ram air rifles, so I'll get in there before someone does, gasrams don't use nitrogen as the propellant.

 

I should clarify, illegal, as in you'd need a FAC for an air rifle using other gases as a propellant, most are S5, such as dart guns for dangerous animals.

 

Help me out here, so its not actually illegal to put anything other than air or carbon dioxide into a rifle reservoir, only if its meant to be under 12ft lb and you don't have a FAC!?

 

What is illegal is the act of making something FAC without the proper paperwork, not putting other gases in the reservoir!

[robbiep]

You're correct in that O2 cleaning is not required for pre-mixed nitrox up to 40%. However, I don't know of a single site that stores pre-mixed nitrox. They all make up your blend by first putting pure O2 into the tank, and then adding air to blend and get the required mix, testing and altering if needed. And by 'NITROX tested' I meant 'O2 cleaned'. Very poorly worded by me.

 

Also horribly poorly worded : I meant to say that the bends was more commonly known of than nitrogen narcosis - among the general public, definitely, and probably amongst divers too, who tend to learn about it, and then forget it all !

I've seen a few people 'get narced', and experienced it myself at about 50 metres. I'd describe it as being pleasantly drunk. I became heavily fixated on my guages, and I could read that I was going too deep for the dive plan, but wasn't processing the information beyond that, to actually do anything about it Fortunately my highly-experienced dive buddy spotted that something wasn't right, and dragged me up to 35 metres, where my recovery was pretty instant.

 

 

Regarding putting other gases into a rifle reservoir : Only a guess from me, but I'd imagine it's to stop (very stupid) people from filling with butane, propane etc. If they did, and didn't blow themselves up, then they could have a 'proper' firearm. But as I say, that's only a complete guess.

[kyska]

 

Help me out here, so its not actually illegal to put anything other than air or carbon dioxide into a rifle reservoir, only if its meant to be under 12ft lb and you don't have a FAC!?

 

What is illegal is the act of making something FAC without the proper paperwork, not putting other gases in the reservoir!

 

You've confused me now Dekers!

 

The way I read it is that any air weapon that uses gases other than air or carbon dioxide are not exempt from licensing, are thus exempt from the firearm certificate procedure. Firearms using other gases are not so exempt.", its academic if it were specially dangerous as you'd need an FAC regardless.

 

Carbon dioxide became exempt from licensing, they were a S1 firearm until this happened, thus, you'd summise that any other gas other than the above would be privy to licensing.

[kyska]

 

 

 

Regarding putting other gases into a rifle reservoir : Only a guess from me, but I'd imagine it's to stop (very stupid) people from filling with butane, propane etc. If they did, and didn't blow themselves up, then they could have a 'proper' firearm. But as I say, that's only a complete guess.

 

Possibly, but also, as mentioned for example, using Argon, which is 30 odd % more dense than air, I imagine that would immediately increase the power of the air rifle, by a lot.

 

So, I imagine its there to stop people filling PCP with higher density gases to gain power, but if examined using compressed air, they would be sub 12ft/lb.

[Underdog]

Adding butane or propane would be less dangerous than pure oxygen!

[bruno22rf]

Pretty sure my mate uses Carbondibakside in his-had to leave the hide twice yesterday

[Bobba]

You're correct in that O2 cleaning is not required for pre-mixed nitrox up to 40%. However, I don't know of a single site that stores pre-mixed nitrox. They all make up your blend by first putting pure O2 into the tank, and then adding air to blend and get the required mix, testing and altering if needed. And by 'NITROX tested' I meant 'O2 cleaned'. Very poorly worded by me.

 

Also horribly poorly worded : I meant to say that the bends was more commonly known of than nitrogen narcosis - among the general public, definitely, and probably amongst divers too, who tend to learn about it, and then forget it all !

I've seen a few people 'get narced', and experienced it myself at about 50 metres. I'd describe it as being pleasantly drunk. I became heavily fixated on my guages, and I could read that I was going too deep for the dive plan, but wasn't processing the information beyond that, to actually do anything about it Fortunately my highly-experienced dive buddy spotted that something wasn't right, and dragged me up to 35 metres, where my recovery was pretty instant.

 

Regarding putting other gases into a rifle reservoir : Only a guess from me, but I'd imagine it's to stop (very stupid) people from filling with butane, propane etc. If they did, and didn't blow themselves up, then they could have a 'proper' firearm. But as I say, that's only a complete guess.

Hi. Many thanks. That clarifies it, and we're on the same wavelength. Our BSAC club stores premix Nitrox and we do tri mix too. My oddest narc was diving Truk Lagoon (sorry!). We were looking at the video clip of a deep dive. The camera told us we were there but neither of us could remember it. Scary stuff!

 

From my knowledge of diving gases I would put nothing through a PCP other than compressed air

Edited August 5, 2015 by Bobba