The choice is yours, but the issue is that removing regs from bottles is dangerous. You can damage threads and you may get in to the habbit of not replacing the loctite or replacing it incorrectly. In my opinion, bottle regs should be left on bottles. Messing around with anything other than burst discs on air bottles should be left to the professionals. So, my point was more to discourage removing the reg than just saying that "I have got away with it".
You are not doing anything wrong by carrying paintball equipment on a plane (as long as it is in the hold and not hand luggage). It is not illegal in anyway. Just ensure that everything is depressurised (including removing any charge from your marker) and remove burst discs to make doubly sure and to be able to easily prove that the bottle has no pressurised air in it.
Then do not declare anything at the check in desk, because you do not have to - you are not carrying any dangerous or illegal items. Declaring that you have a paintball gun in your bag is just folly... if you say this to a check in clark that has no knowledge about the rules and regs of carrying paintballing equipment then you are just going to cause yourself problems.
We have been stopped once (in Montpellier) and were simply asked to open our bags. We did that and once they saw what we were carrying, they sent us on our merry little way.
Like I said Oddjob, the choice is yours - I just wanted to get these points across because a wider audience than just you or me will read this thread.
