AEG not feeding every round in full auto

[marcusr]

Hi all, new to the forum, started airsofting again recently after a 5+ year break.

 

I've had some problems with my AEG since I made some simple upgrades. I have a G&G CM16 SRL with the following changes:

• ZCI barrel
• ZCI aluminium rotary hop unit
• Maple leaf bucking & nub
• ZCI air nozzle

 

The problems only arose after I recently opened the gearbox to shim/grease and replace the air nozzle. The hop and barrel upgrades have been around for a while with no issues.

 

Basically in semi it shoots better than ever, but now in full auto it only shoots an actual BB about 50% of the time (not every other shot, just at random). I would have assumed that it would be the new air nozzle being slightly too long or something, but it shoots 100% of the time in semi so that makes me think the nozzle should be fine?

 

I took a slow motion video of the nozzle moving in semi and full auto. Based on the fact that the piston is stationary after each shot during auto I assume it can't be pre-engagement. I do notice that the nozzle might not be retracting as far in auto. Please let me know if there are any other videos/pictures I can take (in or outside the gearbox) to assist.

 

I'm basically asking if anyone has any ideas for what's wrong, and how I might go about fixing.

 

Thanks in advance for any help!

[Skara]

Did you measure the old nozzle length and buy accordingly?

Also, revert all the upgrades (bar the nozzle) and test every piece individually to see if you can ID the part.

 

You mentioned a ML rubber, which one is it? The older Macarons are notorious for having "too long" feed lips (within quotes because I run them and never had an issue) which affect feeding. The newer Super Macarons seem to have sorted it out, in addition to a larger contact patch and two convenient shoulders inside the rubber for rigidity.

 

Failing all of the above, you may want to add a delayer chip to your sector gear, just be careful to install it the right way (shorter side on the left) otherwise you *may* incur in timing issues, though unlikely after watching those short videos.

 

Another thing, I wouldn't run an aluminium nozzle, if the whole thing is not 100% aligned you risk chewing through hop rubbers like crazy. A simple polymer one with an o-ring will do.

[marcusr]

Thanks for the reply Skara!

 

I didn't actually measure the original nozzle, I just bought this one as it said it was an M4 one and a cursory look online suggested anything from 21.3-21.5 would be fine.

 

I will take it apart again and see if the problem goes away with the stock nozzle. I'm hesitant to go back to it because I've seen a significant FPS and consistency improvement with the new nozzle so would rather solve the issue. The gear delayer sounds like a great idea, would something like this be appropriate?

 

This is the hop rubber I am using. I bought it recently after I ruined the previous (identical) one attempting a flat-hop, and actually installed at the same time as the new nozzle, so maybe I should investigate there too.

[Adolf Hamster]

I wanna say delayer chip, a cycle in semi is gonna be slower on average than in auto (after the first round at least) so if its feeding reliably on semi then it may just be on the threshold of too fast to feed every time in auto.

 

The macarons can occasionally give problems with the longer feedlips, kind of a trade off, most of the time they give a better seal and the accuracy that comes with it but certain guns it can cause issues, although thats usually much worse feeding even in semi if it feeds at all.

 

Way to tell is to drop a round into the feed tube, if it falls all the way through then it wont be feedlips.

[RostokMcSpoons]

I've got a Classic Army m15a3 and a Tokyo Marui Ak47 which are both doing much the same.  Would love to find a fix, though at this point in my revived Airsoft life I've "already got too many guns*"

 

 

* Says no-one, ever

[marcusr]

15 minutes ago, Adolf Hamster said:

I wanna say delayer chip, a cycle in semi is gonna be slower on average than in auto (after the first round at least) so if its feeding reliably on semi then it may just be on the threshold of too fast to feed every time in auto.

 

The macarons can occasionally give problems with the longer feedlips, kind of a trade off, most of the time they give a better seal and the accuracy that comes with it but certain guns it can cause issues, although thats usually much worse feeding even in semi if it feeds at all.

 

Way to tell is to drop a round into the feed tube, if it falls all the way through then it wont be feedlips.

 

So if I take out the hop unit and barrel, hold it upside down, and drop a BB then it gets caught on the end of the bucking (I assume that is the feed lips?). If I push on the BB with a screwdriver it fairly easily falls into the barrel. Should I try to grind down the end of the bucking or could I ruin air-seal?

[Adolf Hamster]

43 minutes ago, marcusr said:

 

So if I take out the hop unit and barrel, hold it upside down, and drop a BB then it gets caught on the end of the bucking (I assume that is the feed lips?). If I push on the BB with a screwdriver it fairly easily falls into the barrel. Should I try to grind down the end of the bucking or could I ruin air-seal?

 

A light bit of pressure can be ok, as long as it's less than what the mag is capable of pushing.

 

I'd avoid sanding the bucking/nozzle, its possible to do so but so very easy to ruin air seal.

 

Worth trying a delayer chip, worst case is it doesnt fix the problem but it wont harm anything either and is the kinda thing i'd put into most builds as a matter of routine.

 

Another thing to look at is the ammo, i've "fixed" plenty of misfeeding guns by doing nothing more complex than emptying the mag and refilling with some geoffs.

[marcusr]

Alright thank you I'll try the delayer. I'm already using what I think is decent ammo.

[Adolf Hamster]

4 minutes ago, marcusr said:

Alright thank you I'll try the delayer. I'm already using what I think is decent ammo.

 

The asg seems popular enough, cant really say havent used anything but geoffs in years, but something to keep in mind as a potential solution.

[Rogerborg]

The other possibility is just that the magazine springs aren't strong enough to shove the BBs up quickly enough, and/or are very slightly misaligned with respect to the hop and magwell.  Have you tried other mags?  Ex-Workmate Eddy's CM16, while a very decent toy, is a little fussy about mags.

[BigStew]

21 hours ago, marcusr said:

Alright thank you I'll try the delayer. I'm already using what I think is decent ammo.

they may have improved but a few sites have banned blasters for miss shapen/ shattering BBs

[EDcase]

Yeah, I know a site that has banned green bottled Blasters for shattering too much

[marcusr]

Oof that's not great. What do you all buy and where from?

[Rogerborg]

10 hours ago, marcusr said:

Oof that's not great. What do you all buy and where from?

 

Anything except those ASG non-devil blasters. It's always hard to be sure, but I've seen an incident of a rental getting fragged in the eyes through a mesh mask, and given that the site handed out 0.2g Blasters and had repeated reports of it happening that day, it's a reasonable assumption.  They seem to get a bad batch every so often, but "it's not all of them" is cold comfort to the targets.

 

PatrolBase is fine.  Outdoors I use bios, Valken 0.25g, 0.28g and 0.32g, and for heavier stuff, Geoffs or Longbow.  Indoors, BAW Bag (yes) 0.2g tracers, and I have some ASG Devil 0.25g Blasters that seem OK.

[marcusr]

On 20/06/2022 at 21:46, Skara said:

Failing all of the above, you may want to add a delayer chip to your sector gear, just be careful to install it the right way (shorter side on the left) otherwise you *may* incur in timing issues, though unlikely after watching those short videos.

 

On 20/06/2022 at 22:06, Adolf Hamster said:

I wanna say delayer chip, a cycle in semi is gonna be slower on average than in auto (after the first round at least) so if its feeding reliably on semi then it may just be on the threshold of too fast to feed every time in auto.

 

Just wanted to say thanks guys, the delayer chip has sorted the issue completely, even with the slightly faster motor I've installed.