I have a bunch of 3000psi and 4500 psi SCBA tanks. I may list some of them in classifieds later but wanted to ask a few questions . The majority of the tanks are 3000psi tanks. Can these be used for PCP guns or Paintball as is or what is needed? I know very little about both sports. I have read that in paintball they could be used to refill smaller tanks but they also seem to have adapters that would allow them to be used for supply? For airgun it seems they are used to refill the gun but once again i am unsure? These bottles have a valve on the top with handle to turn to open or close with a pressure gauge to tell you how much air is left in the bottle. So can anyone explain in both circumstances how they can be used and what is needed?