The Airgun
Unlike most modern firearms that ignite gun powder to create a rapid expansion of gas, an airgun uses stored compressed air, or CO2, to propel the projectile down the barrel. Airguns have come a long way in recent years. Some of the modern airguns are now performing with muzzle velocities greater than 1,400 feet per second. Listed below are four general categories of airguns that are typical.
- Pneumatic
- Spring Operated
- CO2
- Pre-Charged Pneumatic
1. Pneumatic
The pneumatic airgun in pumped by hand, generally 10 pumps, to compress air stored in a cylinder. When the airgun is fired, all the compressed air is released propelling the pellet down the barrel. This firearm needs to be pumped by hand between each shot.
Positives:
- Inexpensive
Negatives:
- Pressure fluctuates depending upon how many pumps you do
- Takes time to reload
- Slower than other types of airguns
2. Spring Operated
The spring operated airgun takes only one pump. By breaking the barrel of the firearm, this compresses a spring. While shooting, the spring pushes a cylinder of air down the barrel. The spring then needs to be re-cocked in between each shot.
Positives:
- Only one pump to reload
- Consistent pressure with every shot
Negatives:
- Airgun is usually heavy
- Spring will get damaged if dry fired
3. CO2 Powered
The compressed CO2 is stored inside a cartridge. Every time you squeeze the trigger, a small amount of CO2 is released propelling the pellet down the barrel.
Positives:
- Quick to reload
Negatives:
- CO2 is affected greatly by temperature (1000 psi @ 85 degrees F vs. 500 psi @ 32 degrees F)
4. Pre-Charged Pneumatic
This type of airgun uses extremely high-pressured air, up to 3000 psi, stored in a tank loaded off a scuba tank or specialized hand pump. Every time you squeeze the trigger, a small amount of compressed air is released propelling the pellet down the barrel.
Positives:
- Quick to reload
- Compressed air acts the same at any temperature
- Generally the fastest airgun available
Negatives:
- Expensive