1) Watch the videos that TF made that are stickied in CCM (this has been said before). They are very informative and give you some needed knowledge on how your marker works.
2) Every time I have seen problems with velocity, I will check the reg first with a reg tester (again, TF has a thread on how to build this) to see if there are problems the recharge or spiking. If the reg is good, then I check my bottom tube and make sure that there is no grease/oil/anything in the bottom tube. Because of the tight tolerances in the bottom tube anything in it will mess with the force that your hammer opens the valve with.
3)If all else fails, talk to CCM. They are great to talk to about stuff like this and always willing to make sure that their products are working at 100%
"I shoot pump because it hurts more feelings." -- ryantuomi (heard at Living Legends 2)
"Not everybody understands English... but everyone understands stick" - Big Sexy Medic
"Pumping is about as much a disadvantage for me as shifting is for a Nascar driver" - Ralanti (in an email between ryantuomi, ralanti and I about playing pump) Thunder Bay Pump Club Dementia Paintball MCB Feedback