CO2 vs. Air: Why Compressed CO2 is Used in Airguns & Paintball

Question
Hi, Ryan.
Why do air pistols, paintball guns etc... use compressed Co2 gas? Why not just compressed air?
Thanks, Ray

Answer
Hey Ray,
       I'm not absolutely sure why CO2 is used instead of oxygen, but I came up with a few reasons based only on my beliefs:
- CO2 is consistent in pressure at the same temperature
- it is harmless in the right concentrations
- it is liquid in the container, allowing little space needed to store it
- oxygen is more useful in hospital and medical settings
- scientifically, the carbon cycle will reproduce any carbon used

Sorry about not having a proper answer for you, and what I have listed are only my beliefs and/or guesses.

     Good luck and hope this helps,

                Ryan