I know the laws because I found them out from our local paintball field.
While driving in a car you must have your co2 unscrewed. It can be full but not into the marker itself.
It is disliked to have the marker right in the view of the public as many people are very etchy about seeing things that look like "guns" in broad daylight. Ya know what I mean?
So yeah, as long as it's unscrewed your not screwed.
