I am sorry, but I am new to paintball. Thus, I will ask some very stupid questions. However, after some research, I have already decided to get a 14" JJ ceramic for my BT-4. I realize, though, that if I were to buy one, I would not know how to go about it. When you try to buy the barrel, it asks what kind of gun you have... but my BT-4 does not seem to be on the list. I know that it is possible because I have heard of other people getting SmartParts barrels and JJ barrels for their BT-4's. How should I go about this.