Colt makes several different models. Which one are you asking about?
Co2 comes out of a bb gun because of the compressed co2 cartridges that are used to propel the bb itself. Additionally, the bb gun that does not use co2 cartridges just doesnt shoot out co2, but air in general.
The Colt 25 airsoft BB gun cost between $10 - $15 depending on the model.
No it won't fire, Co2 is the power source that power the gun.
Colt makes a 1911-A1 Pellet gun made by Umarex. I know of no BB gun unless you are asking about an Air Soft gun. The Pellet gun is very good. I can not answer about an Air soft gun.
Not intended for user to take apart.
No
About 100yd
In the truest sense of the definition of "automatic", no a bb gun cannot be automatic. In function, however, a BB gun can be automatic. A good example would be the Drozd BB gun which fires full automatic, but used CO2 as the power source.
No
Colt has 5 different model Air guns. The Defender is the only BB gun, the rest are pellet guns. Umarex makes all the airguns for colt. I suggest you contact UmarexUSA and ask them for assistance or repairs
Co2 will leak out in a few hours. It's not designed to stay in the gun for a long period of time.
YES! Especially CO2 systems.