Nozzle to bucking fit

[38super]

Question for the techies.

How should the nozzle on an AEG fit with the bucking when it's fully forward?

Should the nozzle go inside the bucking or the nozzle chamfer be just touching the bucking lips?

The correct answer is probably 'whatever gives the best seal' but I'm looking for a guideline here.

RIF is a Cyma P90 with a prowin hop unit and maple leaf bucking. The stock nozzle (20.45mm) has almost no chamfer on it and seems to sit on top of the bucking lips.

The fit looks OK but there is quite a bit of wobble in the nozzle on the cylinder head and I'm concerned that the nozzle doesn't line up properly with the bucking when there is a lot of BB pressure from the magazine pressing on it.

Any help much appreciated.

 

[Rogerborg]

there is quite a bit of wobble in the nozzle on the cylinder head

Taaaaappy tap-tap.

 

[38super]

14 minutes ago, Rogerborg said:



Taaaaappy tap-tap.

Thanks. I've seen that vid. The gun definitely gives the symptoms of very low fps and double feeding if I try to fill the mags beyond about half capacity

What I want to find out is whether the initial fit of the stock nozzle is correct and just try to fix the wobble or should I be looking to get the nozzle fit correct and then fix the wobble?

The nozzle also appears to retract further than necessary to allow a BB to feed. I would have though this made double feeds more likely as it makes more space in the chamber. Should I modify the tappet plate so that the nozzle doesn't retract so far?

 

[Rogerborg]

Are you actually seeing a problem?  A lesson that I've not really learned, but should have by now, is that if it ain't broke[*]then don't try and fix it.

[*] Or sometimes even if it is broke but still works sub-optimally but consistently.

 

[38super]

Are you actually seeing a problem?  A lesson that I've not really learned, but should have by now, is that if it ain't broke[*]then don't try and fix it.

[*] Or sometimes even if it is broke but still works sub-optimally but consistently.

Very inconsistent. Some double feeds. Some bb's just going a few metres. Much more pronounced with full mags. 

Stripped the gear box and found no compression. Going for new cylinder and piston heads. 

I'm mainly wondering if the stock nozzle is suitable for the Prowin/Maple Leaf combo as the stock Cyma nozzle is shorter than most.

Also getting a new piston with a metal rack to have a go at short stroking while I've got it in pieces.