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Hello everyone,
I've been told from many Tanaka users that the PCS valve has a sweet spot, varying from rifle to rifle, at about 70%-85% open.
The reason seems to be that the PCS valve, when not TOO close on the nozzle, will let the entire gas flow in but will work more as a pressure regulator and not as a limiter. Limiting occurs only when the valve spike gets in close proximity of he metal nozzle itself.
Having the PCS valve too open will actually result in less pressure stabilization rather than more FPS. So it seems (experienced Tanaka field operators may chime in in support, of course!).
I searched and searched for a way to determine what the percentage refers to:
1) to the round rigged screw?
2) to the actual valve spike INTO the metal nozzle?
Below is a picture of my current PCS valve position..the valve spike (that you can see when looking through the rubber magazine-to-bolt o-ring) is WAY far outside the metal nozzle, I can practically barely see the tip of the spike.
I fear this is way too open but I don't know if I should take the round rigged screw or the valve sharp "spike" close to the nozzle as reference..
Thanks for the great insights, as usual,
Reezo
I've been told from many Tanaka users that the PCS valve has a sweet spot, varying from rifle to rifle, at about 70%-85% open.
The reason seems to be that the PCS valve, when not TOO close on the nozzle, will let the entire gas flow in but will work more as a pressure regulator and not as a limiter. Limiting occurs only when the valve spike gets in close proximity of he metal nozzle itself.
Having the PCS valve too open will actually result in less pressure stabilization rather than more FPS. So it seems (experienced Tanaka field operators may chime in in support, of course!).
I searched and searched for a way to determine what the percentage refers to:
1) to the round rigged screw?
2) to the actual valve spike INTO the metal nozzle?
Below is a picture of my current PCS valve position..the valve spike (that you can see when looking through the rubber magazine-to-bolt o-ring) is WAY far outside the metal nozzle, I can practically barely see the tip of the spike.

I fear this is way too open but I don't know if I should take the round rigged screw or the valve sharp "spike" close to the nozzle as reference..
Thanks for the great insights, as usual,
Reezo