G+G L85 blowback solution

[1st Commando]

Ok this is not entirely mine as the plate was made and fitted by another technician but here is the alternative to having to dissconnect your blowback (i never dissconnected mine anyway)

 

 

 

here you can see the brass plate he has fitted to the front of the blowback follower upon which i have affixed some double sided sticky tape to catch any fragments should the hook break

[fnfr3ger]

a nice solution for the problem and will g&g do something similar when they make sure that the prob won't occur anymore ?

[1st Commando]

so i'm told this is similar to the solution they have planned

[fnfr3ger]

ah ok and thanks for the quick response mate !

[fnfr3ger]

i sent an email to g&g about the l85a2 and they didn't respond , some emails later i finally got a response and since the g&g review thread is gone i'll post it here

 

Hi ****,

 

Thank you for your e-mail.

Now we can let you know we will design the L85A2 and susat.But we will check the price in the future.

Thank you.

Allen

G&G ARMAMENT

[The Chef]

I have just taken delivery of my new L85A1 and upon removing the TMH, it appears to have this very thing covered up already.

 

Not sure how this differs from the original versions, but it may well be G&G have actually sorted a problem out, jolly good of them.

 

Anyhows, here's a pic of the top of my mechbox.

[The Chef]

oh well, less than 50 rounds through it and gears have stripped.

 

all teeth gone from the spur gear and one from the sector gear.

 

Blowback mechanism is still OK though. Although I will be disabling it.

 

There appears to be a slight wear mark on the second tooth on the piston though, as if the sector gear has struck it rather than meshing properly.

 

Anyhows, G&G have been contacted and hopefully they will send out some new stuff. pity its not the same as other stuff, because I am convinced G&G gears are monkey metal.

[Stealthbomber]

Who at G&G did you contact?

Did you buy the gun in the UK or from HK?

 

Oh, and there's nothing covering the top of the gearbox in your gun. That's how the standard gearbox looks.

[The Chef]

Just their main email addy. Done it before with an M14 that went a bit funny. They are very good with aftersales service.

 

I got it from WGC, which is why I have gone straight to them direct rather than trying to return it.

[bellyisking]

generally if you got an l85 making a humming noise and not fire what so ever, i'm assuming the gears are strippted or the cylinder is gone bust?

[The Chef]

well, it will be a buzz if the gears are stripped, you'll know it for definite.

 

if its more of a low hum, it could be the motor jammed.

 

so the choices are,

metallic whirring buzz = gears gone

low electric hum = motor jammed.

 

possibly!

[Stealthbomber]

Most likely cause of a buzzing noise inside a G&G L85 is that the piston has worn away.

[bellyisking]

well that's ######, only had it two weeks, and it now bust, great. i hear using a better piston build can only lead to worse things, eg both gears and cylinder go boom, can anyone one confirm this? or maybe where i should go from here? last thing i want my l85 to eat piston like no tommorow, but heck i got a year warrenty, should i just send it back get the refund and wait for the ics?

[WildCard]

Well i blew 4 pistons... i'm waiting for G&G to bring a solution

[WickedBassie]

I tried to find the cause of Wildcards L85 excessive piston consuming...

 

We had several possible causes.

 

1. Piston is going too far forward, so the gears collide with the top of the rear tooth.

 

2. The gears are spinning too fast, and catching up with the piston when not yet in

the most forward position.

 

Both of them were not the cause of the problem.

 

1. is just not possible because the dimensioning of the gearbox does not allow this much room for the piston to move this far forward or upward. So the gears cannot touch the top of the teeth.

 

2. the spring and piston are moving so fast that the gears cannot in any possible way catch up with the piston before it has reached the resting position.

[Stealthbomber]

As I keep saying, I'm pretty sure the problem is that the dimensions of the gearbox are slightly wrong.

The piston is sitting slightly too high.

Every piston I've damaged so far has showed severe wear to the bottom 1.5mm or so of the teeth but the rest of every tooth is untouched. The sector gear just doesn't seem to engage the piston properly.

 

I have a set of PSG1 gears on the way, to see if they fit. I didn't see the point in obtaining another set of G&G gears at this point. If they're the same as the old ones, what'd be the point?

I'll see if the PSG1 gears make a difference. If they don't I suspect we'll end up waiting for G&G to bring out a sector gear with a slightly bigger diameter.

 

Which reminds me, I suppose I'd better order another piston to go with the new gears. I think I'll try an SR25 piston this time.

[sadigh]

Just been thinking Stealthbomber, are you sure thats a wise idea?

 

I mean, if the sector gear is too small in diameter, then surely the gearbox shell itself is not dimensioned properly either? By that I mean that the hole for the sector gears' bushing to sit in may be 1.5mm below where it should be.

 

If you did use a sector gear that has a slighltly wider diameter, then surely the teeth on it would mesh deeper with the teeth on the spur gear, and cause the sector gear to be slightly off centre on its axis, and resulting on more stress being exerted onto the spur gear?

 

It sounds to me that G&G made abit of a cock-up on the dimensioning of the gearbox shell itself, rather than the gearset, but I may be wrong of course. Just purely sharing my view. I mean, it may be better to wait to see what G&G have to say on the matter before splashing out on a new gearset and piston, which may eventually strip as well.

 

EDIT - sorry for the poorly constructed post, it's difficult to explain what I mean

[Stealthbomber]

There's 2 sets of teeth on the sector gear. If they made a sector gear with the teeth that engage the spur the same size BUT made the teeth that pull the piston slightly taller it'd work a lot better IMO.

 

There's nothing else for it really. I suppose it is theoretically possible to mill the mating surfaces between the top and bottom gearbox sections and adjust the fit but it's not really feasible.

 

I suppose it's possible that the piston rails aren't the correct size and it's allowing the piston to lift up and move around inside the cylinder. Maybe this'd be easier to fix if they redesigned the upper?

 

It's just my own opinion but the 3 pistons I've had inside mine have ALL shown big signs of wear on the bottom of the teeth and none on the top. To me this says the teeth aren't meshing properly.

[sadigh]

Ahh ok I see what you mean about the sector gear teeth, didn't think about it like that before. Yeah I agree with you though about the incorrect meshing issue, I was trying to get at that in my post but it came out abit messed up and confused, its been a hard day.

 

I hope the new gear set turns out ok for you though, it would be interesting to see if the teeth that engage with the piston on the Marui PSG1 sector gear are longer than the G&G L85 sector gear.