Pneumatic cannon

Pneumatic ball valve cannon

A pneumatic cannon is a cannon powered by pressurized gas, usually air or CO2. They are more complex than combustion cannons but also more powerful, and their performance is more consistent.

Pneumatic launchers consist of five basic elements:

• Compressed gas storage reservoir (chamber for short)
• Filling valve (bicycle Schrader valves, quick disconnects, etc.)
• Firing valve (ball valves, sprinkler valves, piston valves, bolt-style valves(see piston valves) quick-exhaust valves, and burst disks are the most common)
• Barrel
• Pressure gauge (for safety & repeatable launches)

In order to fire, the operator loads a projectile into the barrel, fills the chamber with a compressed gas (air compressors, hand pumps, regulated bottled gas, and 12 gram CO2 cartridges are common filling methods), and activates the main valve thus dumping the air in the chamber to the barrel.

The expansion of the compressed gas propels the projectile down the barrel. The barrel length determines the amount of energy transferred to the projectile and ultimately the velocity of the projectile.

High performance launchers use techniques such as modifying valves for faster opening times, using homemade valves, and maximizing the amount of airflow through the valve.

The GGDT (gas gun design tool) is highly recommended to those interested in pneumatic launchers.