Best nozzle to replace CYMA M14 stock nozzle?

[Troy T. Moore]

I am working on a gun for a friend of mine. He wants it shotting in the 380-400fps reange. No problem, right?

Stock it was 340fps. Take it apart and put in new piston, piston head, spring guide, cylinder head, tappet place and nozzle. All parts are Guarder brand. Put in Modify M120 spring which is significantly "stiffer" than the stock spring.

Clean out the green goop. Shim and lube with PTFE synthetic lube.

Humpty dumpty gets put back together...

Shooting 300fps now...

I looked at the nozzle and noticed the end is more tapered than the stock one. I have had this apart and back together a couple of time, shaved the front of the tappet plate a bit to try and gain some length. I am 90% sure this is where my problem is, the nozzle is not seating properly against the hop up rubber. With calipers it is apparent that the Guarder nozzle is a fraction of a millimetre shorter as well, which does not help.

Which after market nozzle will work better? I also am shocked to see the Guarder nozzle does NOT have an o-ring to seal on the cylinder head.

I do loads of gundocing, mostly AKs and some M4/M16s. I have only worked on a CA M14 in the past which was an adventure in itself. I almost forgot how much I hated working on the M14 style AEG...

Any and all help appreciated. Thank you.