Exact same mod as on GBB pistol! Just bigger and easier! But to be honest, it was my first try in life as doing this mod and the first one leaks. The second didn't. The difference was that the first one I completly disassemble it and when reassembling it start leaking from the back of it. No link with the mod. The second one I didn't disassemble it and it still works wonder!
If I can suggest you, do this mod first and look for the fps gain. The noozle plastic valve is more annoying to do and don't give any noticable fps gain. But you can also shorten (trim) the noozle bulbs about 1mm each side. This will allow the valve to stay open longuer, maning more fps! But if you cut too much fps will lower a lot.
I tried many things on it
