I have a couple of questions about my new GG...first, what are the two adjustment rings on the push button for? How should they be adjusted? And second, I noticed under the top cap, there is another adjustment screw. What is this for? I have noticed that my VPX tank won't fire unless I loosen it several turns, then it wobbles...no good! Is there a way to adjust this? I have a Protank II that seems to be working fine! 