After reading the article The Difference Between Using CO2 and Compressed Air, you should have a good idea of the differences between the two pressure sources. While CO2 is more convenient in some cases, it pales in performance to compressed air (also known as HPA). In use an HPA Tank is similar to a CO2 bottle; you screw it into the ASA and go. However, a few safety precautions need to be observed to make your enjoyment of paintball go much more smoothly!
Compressed Air Safety
A quick inspection of your Compressed Air Tank should be done at the start of every game day. Take a look at the top of the valve, the ASA threads and the gauge for any cracks or signs of stress. The fill nipple should be clean of debris. A fiber wrapped tank should be free of cracks and serious dings or chips. A few minor scratches can be expected but any chip that reaches the fiber threads underneath the clear resin exterior means that tank is condemned.
This is why you should always buy a paintball tank bottle cover for your HPA tank. All it takes is one drop, one trip and fall, one slip of the hand for your expensive investment to become unsafe and ruined. Most tank covers are made of neoprene or other material, usually with additional padded sections for extra impact protection and non-slip butt areas to stay put against the shoulder. It’s a sad fact that many tournament players simply put athletic tape on their HPA tanks for grip, claiming that they needed it to be lighter and less drag when switching between firing left or right handed (we won’t talk about how it makes it easier to wipe a hit!). That’s great when playing on artificial turf. Playing in an environment full of rocks and other hard hazards is a different story. A reputable field will be doing a quick inspection of HPA tanks when they are brought up to the fill station and I have seen many a player’s tank get refused because of damage that a simple $10-20 cover would have avoided. Forget what the ‘pros’ do and get a cover! Even if you mount your tank in a pouch on your tactical vest for use with a remote a cover is not a bad idea, either, as plenty of tanks roll out of a car or get dropped by accident off the field.
Know the pressure rating of your tank! It should go without saying but some people still mess this up. At fields with self-fill stations you need to be sure you only fill to the proper pressure. At fields where the staff does the filling you should always mention whether your tank is a 3000 psi or 4500 psi when you hand it to them as a reminder, since they might be filling many tanks quickly between games and sometimes get sidetracked.
Sometimes after getting a fill and disconnecting you might hear a slight hissing from the fill nipple. There is an o-ring on a little piston in this piece that on occasion needs to be replaced (it’s a good idea to carry a spare in your kit bag). Never put any oil or grease in the fill nipple to stop a leak! Oil or grease in the fill nipple will be blasted into a mist from when high pressure air starts rushing through. Tanks heat up when filled to pressure, and if it gets hot enough this oil mist gets can ignite, similar to how a diesel engine combusts. So remember, NEVER PUT ANYTHING IN THE FILL NIPPLE!
Compressed air is much more stable than CO2 in all weather conditions but being exposed to extreme heat can still overpressurize the vessel to the point of blowing a burst disk, as well as degrading the seals. Therefore, just like a CO2 bottle you don’t want to leave your HPA tank in a hot trunk of the car or laying in direct sunlight during high heat conditions.
A compressed air tank’s physical size can be a challenge for smaller players. The trend of the last few years has been to ditch the drop forward and go to an ASA mounted directly below the grip. This set up has some advantages such as a lower height, ease of switching left or right handed and more compact profile. Many players like to trash talk the drop forward without realizing that many player’s benefit from them! A prime example is shorter adults and youth paintball players. Even a small 45 ci 4500 psi HPA tank can be too long to shoulder properly for players short in stature. Consider this option if the overall length is too much.
When air is compressed it heats up. You will notice that your HPA tank is warm or even hot to the touch when freshly filled. When the tank cools down to ambient the pressure will drop. We have seen 4500 psi tanks drop over 1000 psi after cool down. The best way to alleviate this is to fill your tank slowly but this is not always possible. When a field staff member is working the HPA station and there is a line of players waiting for fills he or she is probably going to go as fast as possible. Just like CO2 bottles you should try to fill your HPA tanks as soon after arriving at the field as possible. That way you can get them topped up before game start so you enter play with as many shots as possible!
Watch your tank’s gauge! Even though it will continue to put out pressure until it reaches zero the consistency of the output will start to waver as you dip below the tank’s output pressure. Most fields have an ‘all-day air’ policy so top up whenever you can.
The fill nipple is a one way valve through the reg and into the tank’s bottle itself. Dirt, metal shavings and other crud in the fill nipple will be blown into the bottle, then go out through the regulator and into your marker. This debris can wreak havoc on your seals and other internals of both. Preventing this is easy. A simple fill nipple cover will keep the crud out. There are several styles to choose from, such as simple rubber covers, slip on metal covers or snap on metal covers. One hint… people working the fill stations forget to put nipple covers back on all the time. Look around any fill area and you will see a pile of them. Get into the habit of taking it off before handing your bottle to them to be filled or invest in a cover with a leash.
Protecting Your Tank
The valve on your CO2 tank is typically made of brass to reduce wear on the ASA. A ding or dent on the lip where the sealing urethane tank o-ring sits can cause your tank to leak and is not repairable short of replacing the entire valve. To prevent this you should always use an aluminum or plastic paintball tank thread protector cap for each of your tanks. Such an inexpensive little item can save an entire day of paintball play!
If your CO2 tank does get a ding on the lip and has trouble sealing then one old trick is to lay an extra o-ring flat in the bottom of the ASA. When you screw your tank into place it will seal against the face of the valve. You will go through a lot of o-rings this way but it will get you on the field.