Can nitrogen be used in PCPs?
by B.B. Pelletier
This report was requested by Pestbgone, but, from my years working at AirForce, I know that a lot of shooters also wonder about it.
Here's the argument: Air is composed of approximately 78 percent nitrogen, 21 percent oxygen and the remainder a smattering of other gasses. With nitrogen as the principal component, they want to know why a precharged airgun can't be operated on it exclusively. I will answer that today.
What I used to tell people who called in with this question is that we only recommended our guns for use with breathing air and no other gasses. The seals in our guns were selected for use with air (true) and we couldn't be responsible for their use with any other gas (also true).
Do you have any idea of how much money an airgun manufacturer pays EVERY YEAR for liability insurance? I won't tell you, but it's a heck of a lot more than many of you make in a year. I'm not talking about the level of liability, now, just the cost for the coverage (the bill)! The cost is based in part on how many guns you expect to sell, so as you prosper, your rates increase because the insurance company's exposure increases.
Just to get covered, a company has to have solid literature, solid technical data on its products and a solid base of customer information that directs the customer in the safe use of the product. Remember, and this is no laughing matter, that there once was a man who sued a lawnmower manufacturer for damages he received when he picked up the mower deck while the lawnmower was running in an attempt to trim his hedges! He won a settlement for that! That's why all mowers sold in the United States today have a kill switch that must be depressed at all times for the mower to run. It's that bar you have to squeeze when operating the mower.
So, is nitrogen dangerous?
Will nitrogen hurt your PCP? No, it won't. Nitrogen is an inert gas that doesn't react with most things. Oxygen, on the other hand, supports combustion, and the oxygen that both medical personnel and welders have access to has been known to blow up airguns!
Oxygen can kill you!
Now, here is the bad news. Do you think that nobody would be stupid enough to use straight oxygen in a PCP? Think again. It has happened many times, once probably resulting in death. That one happened in England in the 1990s, but look at Pyramyd Air's experience with it.
This Fire 201 9mm rifle was filled with oxygen instead of air. The caliber doesn't make any difference. It's the oxygen that does the damage.
This is what happens when a VERY HOT flame is held against aluminum for a long time! It looks like a cutting torch has been used on this gun from the inside out. This was a Fire 201 9mm rifle.
Note the discoloration of the anodizing. Forensic scientists use clues like this and the bending of the steel barrel to determine how much heat caused the damage and how long the fire lasted.
This is the SECOND time Pyramyd Air has had to deal with this same problem. The first time, a medical technician called in to ask them why his Career 707 was shooting a blue flame out the muzzle on every shot!
So what? We're talking about nitrogen
What this has to do with nitrogen is this. Simply this, people don't pay attention! Nitrogen can come in tanks compressed to 6,000 psi instead of 3,000 psi. I once met a guy who thought the way to fill a PCP was to connect the hose to the gun and open the valve as fast as he could. The gun filled right up in a couple of seconds, though it did get hot. If you don't understand why, please re-take your high school science class where they explained about the heat generated by compression.
Now, you take a paintball player who has access to nitrogen in 6,000 psi tanks and the same attitude as the guy I just described, and you'll have large pieces left to bury. But, take a medical technician with the same attitude and access to pure oxygen and the pieces will be both smaller and probably toasted.
What about other gasses?
What about helium? Yeah - what about it? Will it make a pellet go faster? Maybe. Do I care? No. I have firearms for whenever I need to go faster or hit harder.
Show some respect
Guys, these are AIR guns, and they need to be operated with some respect. Yes, the shark blowing up in Jaws was Hollywood theatrics, but we are dealing with some serious technology here, and we need to respect it. It's funny watching someone else on YouTube shoot a propane tank with a .22 rimfire and getting consumed in the resulting explosion, but it's not as funny when you're the one at ground zero.
So, what am I saying? I'm saying that our current precharged airguns are built to operate on breathing air and that's how they should be used. Let's leave the serious accidents to the skateboarders, stunt cyclists and America's Funniest Home Videos.