CYMA MP5 SD6 thoughts

[Sewdhull]

Agree you need the bearing for consistency and reduce chance of the spring getting hiccups

For the 18 AWG Perun wires I actually appreciate they put this in, this is some very high wire count with silicone jacket so it's very flexible which is great for working with, and I've calculated the difference of ohm between 18 and 16 AWG for the lengths in airsoft is really negligible

Have you tried polishing the piston groove walls on the gearbox and where the tappet plate and selector plate slides on? I touched up mine with some 5000 or 7000 (forgot which one) papers and it does make things glide on the gearbox better (now I actually have a problem with an overpowered m90 spring shooing 355 FPS because it is too efficient but that is another topic)

The currents in aegs aren't usually very high so the perun is fine.

I haven't done anything to the gearbox grooves other than check the piston slides properly. Perhaps I should.

I'm trying to be mechanically sympathetic to the gearbox and using the lowest spring stiffness I can.

 

[Sewdhull]

Ok, so I went with M105 spring from xt. Very consistent at 1.18 and 1.19J on .25 with hop off.

I could only find .4g bbs but they gave me 1.17 and 1.18J.

I still have to hop it so this is the peak energy and hop will scrub some off.

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[Sewdhull]

View attachment 124417I'm not convinced it's feeding quite right, it seems to but the hop rubber pokes back further than I think it should

 

[Sewdhull]

Numbers, 1 to 4 are semi.

5 to 7 3rd burst, or maybe the 1st 3 are burst ...

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[Lozart]

View attachment 124417I'm not convinced it's feeding quite right, it seems to but the hop rubber pokes back further than I think it should

Maple Leaf?

 

[Sewdhull]

Yes indeed, I've others I can try 

 

[Lozart]

Yes indeed, I've others I can try 

Maple leaf are notorious for this. Prommy purple used to be the problem child but ML were just like "hold my beer".

 

[Sewdhull]

I'll have a close look at the hop bucking nozzle on the morrow, take some measurements.