Two of the most asked questions from new paintball players are, “What’s the difference between CO2 and compressed air” and “Which is better, CO2 or compressed air?”
CO2 and compressed air (HPA) are high-pressure gases that are required to power paintball guns.
When CO2 is stored in a CO2 bottle, it is in liquid form. Letting only a little CO2 out of the bottle at a time allows for just gas to come out. This gas is what’s used to fire the paintball marker or paintball gun.
CO2’s biggest problem is the expansion from liquid to gas. For this transition from gas to happen correctly, it needs to be warm, around 75°F (23°C). So if you play in cold weather, this expansion will not happen correctly, and there will be a drop in PSI, and the paintball marker’s performance will suffer.
CO2 also suffers at high rates of fire. The faster the CO2 changes from liquid to gas, the colder it gets, resulting in a drop in PSI. In other words, the quicker the gun is fired, the colder the CO2 tan will get. When used on mechanical style guns in the summer, this is fine, but electronic markers with a higher rate of fire will suffer more from the drop in pressure.
CO2 tanks do, however, have some advantages. The main reason people end up going with CO2 is that it has a considerably lower startup cost. The 20oz CO2 tank is the most popular size; it’s sold for around $22 and can shoot 1000+ paintballs. The amount of shots/cost is an excellent way for players that play on private property to play a lot of paintball for little cost. You could pick up a few CO2 tanks and play all day. Refills can cost anywhere from $3 to $7. If you don’t have a paintball shop or field nearby, many welding and fire extinguisher supply companies can fill CO2 tanks.
Compressed air tanks started gaining popularity in the early 90s. When paintball guns began to shoot faster, the drawbacks of CO2 became more apparent. Compressed air is also known as High-Pressure Air (HPA), Nitro, N2 or Nitrogen Tanks they are all the same thing. Compressed air is just what it sounds like, compressed atmosphere.
Tanks come in many different sizes and are found in 3000 PSI or 4500 PSI. The difference 3000 PSI and 4500 PSI is not the output pressures but the pressure that the tank can hold, so the 4500 PSI results in more shots than the 3000 PSI. Think of it as packing more air in the 4500 PSI tank but still only allowing out the same amount.
Compressed air’s main advantage is consistency. The more consistent pressure results in much more consistent performance. Compressed air is marginally affected by temperature, unlike CO2, making it great for cold weather and electronic guns. Most paintball fields charge for all-day compressed air fills. A flat rate is paid at the beginning of the day, typically $5 to $10, and you can fill your tank as many times as you like. While the initial cost is more, you could save money going with compressed air in the long run.
The downside of compressed air is the initial cost. Tanks can range anywhere from $40 to $250. To get as many shots on compressed air as you would that 20oz CO2 tank, a 68 CI 4500 PSI compressed air tank is needed.
Another important note is that some guns will only work with compressed air. A general rule is that most electronic paintball guns should use compressed air, and mechanical guns can use either compressed air or CO2.