I have installed regulators in 4 Royals by now. I also opened some factory regulated FX guns. There is a difference between the instructions available on fx site for installation of regulator and the way fx installs regulators in their own factory.
FX advises to drill the breathe hole and remove the gas kit seal ring and install the regulator. While I have seen that factory regulated fx guns normally has a washer between the regulator and the bottle adopter. It pushes the regulator and does not allow the regulator come towards the adopter of bottle.
The design of fx regulator reflects that the air from regulated chamber should not release even if the bottle is removed but in some guns it releases and in some it does not. I feel that the release of air from the regulated chamber on removing the bottle is because the regulator moves towards the adopter as the unregulated air pressure is no more there.
If we put a washer of around 0.9 mm thickness between the regulator and the adopter, I feel that the regulated chamber will hold the air pressure even if the bottle be removed.
This arrangement may also decrease the extreme spread of the gun.
FX advises to drill the breathe hole and remove the gas kit seal ring and install the regulator. While I have seen that factory regulated fx guns normally has a washer between the regulator and the bottle adopter. It pushes the regulator and does not allow the regulator come towards the adopter of bottle.
The design of fx regulator reflects that the air from regulated chamber should not release even if the bottle is removed but in some guns it releases and in some it does not. I feel that the release of air from the regulated chamber on removing the bottle is because the regulator moves towards the adopter as the unregulated air pressure is no more there.
If we put a washer of around 0.9 mm thickness between the regulator and the adopter, I feel that the regulated chamber will hold the air pressure even if the bottle be removed.
This arrangement may also decrease the extreme spread of the gun.