Help, Lower FPS Kwc Pt92 (fixed)

[dale]

I need help lowering the FPS on a KWC PT92, I've seen the same gun ranging from 300-400 FPS, mine fires on the high end.

What regulates the FPS so I can just buy that part or can anyone tell me how to modify it and drop the FPS. 

I've seen many videos and pictures on modifying the valve but non seem to match the nozzle set up mine has.

There are no springs/screws or pins in the nozzle, below is how it breaks down.

Any help would be greatly appreciated.

View attachment 65716

 

[jsmithski]

Take a m4 or m5 set screw, cut the end of it so it becomes hollow. Screw it in the end of the nozzle to restrict the flow.

 

[Adolf Hamster]

Take a m4 or m5 set screw, cut the end of it so it becomes hollow. Screw it in the end of the nozzle to restrict the flow.

Click to shrink...

won't that block the float valve from closing?

i've seen that design before and best i can make out the float valve is opened by the round in the chamber so you need to have the nozzle open.

 

[jsmithski]

won't that block the float valve from closing?

i've seen that design before and best i can make out the float valve is opened by the round in the chamber so you need to have the nozzle open.

Click to shrink...

Damn, you may be right, that design is weird. So maybe shave some of that rod, the valve will open a bit less and close faster afterward.

 

[Adolf Hamster]

Damn, you may be right, that design is weird. So maybe shave some of that rod, the valve will open a bit less and close faster afterward.

Click to shrink...

i'd check you can get a spare for it before giving that a go, but the logic seems sound enough.

 

[jsmithski]

OK so maybe add an oring on the rod where it seals with the nozzle? Or even better mold it precisely with sugru. I would try that for sure.

 

[dale]

Thanks for the advise so far, i can buy another floating valve so that s always an option. But the cybergun PT92 is just a rebrand and ive seen them rated at 340 Fps. Does anyone know what the system is on that and why its 60-70 FPS lower.

 

[dale]

I did a lot of searching for parts and noticed a slight difference on some valves compared to mine. luck would have it i found a CQB valve on https://www.thingiverse.com/thing:4364423. Got it 3D printed and it seems to have solved the issue

1.3 joules down to around 0.9

the original part is the black one

View attachment 66283