I have included links to FX Dreamline/Crown tuning videos which should answer some questions about the basic "how to"s and concepts(how the relationship of regulator pressure to hammer spring force can affect speed, shot count, extreme fps spreads, etc...) of tuning these FX guns. These are just a few that I have found very useful, but are by no means the only ones out there, so I encourage you to research other videos and articles which may be tailored more to your specific needs.
https://youtu.be/xxi3Vj0lkVI
*LOWERING* regulator pressure- Please note the above video from Ted was made 4 years ago before FX started using the "newer" AMP regulators in their guns. He states that lowering the reg pressure(of the "older" regulator) without depressurizing the tank can ruin the airgun. You will hear from Steve(AEAC) in the following videos that is no longer the case with the "newer" AMP regulators(although he does recommend lowering the regulator adjustment screw by no more than 1/4 turn at a time, then dry firing a couple times to let the reg "settle" or stabilize).
*RAISING* the regulator pressure while the tank is pressurized was never an issue, even on "older" style regulators.
https://youtu.be/Dzs_muWHE5s
https://youtu.be/rcyDUefHmSE
I'd encourage anyone thinking of "tuning" their FX Crown or Dreamline to thoroughly watch these videos and keep referring back to them as needed.
Good luck
https://youtu.be/xxi3Vj0lkVI
*LOWERING* regulator pressure- Please note the above video from Ted was made 4 years ago before FX started using the "newer" AMP regulators in their guns. He states that lowering the reg pressure(of the "older" regulator) without depressurizing the tank can ruin the airgun. You will hear from Steve(AEAC) in the following videos that is no longer the case with the "newer" AMP regulators(although he does recommend lowering the regulator adjustment screw by no more than 1/4 turn at a time, then dry firing a couple times to let the reg "settle" or stabilize).
*RAISING* the regulator pressure while the tank is pressurized was never an issue, even on "older" style regulators.
https://youtu.be/Dzs_muWHE5s
https://youtu.be/rcyDUefHmSE
I'd encourage anyone thinking of "tuning" their FX Crown or Dreamline to thoroughly watch these videos and keep referring back to them as needed.
Good luck