Increase Joules power of my HK417D GBBR VFC

[Lucky]

Hello!

I’ve just bought the HK417D GBBR VFC (1J version), and i would like to know if there is a way to increase the joules power. I thought that maybe setting up the NPAS could allow me to do that. Or maybe i can change the gas valve, IDK…

Has anyone an idea?

And do you know what are the different pieces between this 1J version and the 1.3J version that makes the power change? 
Thank you for your answers

[BigStew]

There are multiple ways depending on how mechanically skill you are (all methods require a chrono). 1 use a more powerful gas( not a bad idea to have a variety of gases for different ambient temperatures). 2 fit an adjustable NPAS (would be my choice). 3 change the knocker valve spring to release more gas per trigger pull (no on the fly adjustment could suddenly find your gun is hot and unusable). 4.  probably best way to get consists power would be to fit HPA valves to the mags( but HPA).

[Lucky]

1 hour ago, BigStew said:

There are multiple ways depending on how mechanically skill you are (all methods require a chrono). 1 use a more powerful gas( not a bad idea to have a variety of gases for different ambient temperatures). 2 fit an adjustable NPAS (would be my choice). 3 change the knocker valve spring to release more gas per trigger pull (no on the fly adjustment could suddenly find your gun is hot and unusable). 4.  probably best way to get consists power would be to fit HPA valves to the mags( but HPA).

Ok, i already have a NPAS on my HK417 so i’ll try to set it up. And i will think about buying a new HPA valve.

Thank you for your answer! 😁

[hitmanNo2]

Don't VFC offer different power nozzles?  Low, 1J, high etc?