Gnu(s) possibly double-feeding - BBs jammed in the barrel

[RostokMcSpoons]

I had this happen on my F2000 when I was using a very old and perhaps rather tired Classic Army STANAG high cap, and yesterday it happened with my TM AK47 with its original (and thus also rather old) high cap mag... happily firing away on semi, but switching to full auto I've ended up with a 2 or more BBs jammed in the barrel.   Easy to clear the F2000 thanks to its construction, but an utter pain on the AK as the BBs haven't popped out when using the unjamming rod - so I'll be disassembling the gun just to get rid of a few BBs.   Arrghhh.

Now it could be I'm just being unlucky with some of the cheapo BBs I'm using up.  Gold Fire and Bulldog 0.20g at the moment.  The TM has a tight bore barrel, and when I first used it a gazillion years ago it clogged up a couple of times until I switched from the cheap stuff back to TM BB's.
And it could also be that I'm just having a quick test fire, so there aren't many BBs in the mags, and I'm not winding them up fully, so I might be encouraging a mis-feed once I'm in to a longer burst, and there's not enough to shove the BBs up into the hop unit properly.

Or it could be that I've taken both apart, and I've upset something.

Obviously I can just stick to newer (and hopefully better) ammo,  load more in the mags and wind them up more (oh, and ditch the old CA mag as it's definitely looking its age), but is there anything else I should look out for? 

What could I have upset in the guns?   If the AK motor isn't running freely could that cause it?

 

[Hudson]

Ammo is the first thing to look at.

Now it could be I'm just being unlucky with some of the cheapo BBs I'm using up.  Gold Fire and Bulldog 0.20g at the moment.  The TM has a tight bore barrel, and when I first used it a gazillion years ago it clogged up a couple of times until I switched from the cheap stuff back to TM BB's.
 

I think you've identified the problem yourself.

Only use decent ammo, it's too expensive to use cheap ammo.

 

[Adolf Hamster]

I'm inclined to agree.

There may well be something else going on, but ammo is a relatively easy thing to take out of the equation.

 

[Ebeneezer Goode]

Not sure about the other ones, but bulldogs are fit for the bin. Or maybe at a push grenades...

Always use good quality ammo. Will solve most of your issues I suspect.

 

[concretesnail]

It'll be the bbs causing it, the cheap bbs are usually poor. Stick to better quality bbs and you'll have fewer issues I'm sure.

Good good getting everything cleared.

 

[RostokMcSpoons]

Cheers guys

The thing is I know the Gold Fire stuff is old and cheap (came from my loft, so more than a decade old) and the Bulldog stuff is crapola, but I have already gone through a lot of rounds of each with no problems I can remember.   Most of it will have gone through the DE M906 though, which might be a bit more forgiving (I don't think its tight-bore barrel).

 
I might just be unlucky now that it's happened a couple of times in quick succession, on different guns, so it's probably impossible to infer anything from that, but I thought I'd ask, just in case there's anything else.

 

[Adolf Hamster]

which might be a bit more forgiving (I don't think its tight-bore barrel).

it's entirely plausible that some guns will be better at handling bad ammo.

especially as you start pushing for more performance they can become fussier eaters.

 

[RostokMcSpoons]

Is there a trick to unjamming the barrel?

Obviously I've pushed the unjamming rod down the barrel, having dialed out all the hop. I can now see a BB wedged at the top of the feed tube but not sure how to get it out of there, as I suspect there's another BB in the barrel pressing against it.

I don't want to push too hard anywhere in case I bugger the gun altogether, but taking it apart is a bit of a ball-ache due to the fake bolt handle gubbins.

Could I split the BB with a sharpened screwdriver and a bit of a tap?

(Hah, I've said all that but I do have to break open the gearbox in case there's a shim gone walkies.  Call it 'for future reference'!)

 

[Ebeneezer Goode]

Thats odd for it to be so badly jammed. I wonder if a BB may have split/disintegrated in there.

Have you tried putting the rod up the feed tube and seeing if you can nudge things along? Disassembly may be you're only option at this rate.

 

[RostokMcSpoons]

Thats odd for it to be so badly jammed. I wonder if a BB may have split/disintegrated in there.

Have you tried putting the rod up the feed tube and seeing if you can nudge things along? Disassembly may be you're only option at this rate.

I did end up taking it... just two BBs in there, and I could already move them around against the nozzle, they just refused to drop down the feed tube.
I even fashioned a spring hook from a bit of dowel with some bent guitar string attached to the end, but I couldn't coax them out of there.   (If someone can manufacture a BB-puller for this situation, they could surely earn a few quid, certainly I'd be first in the queue)

Anyway, AK now in bits, barrel given a quick clean with bit of cotton.

I've mentally noted not to use cheapo BBs in that gun every again, and it's all ready for my next (cosmetic) purchase to arrive... if I go ahead with it that is.  New thread *** incoming ***

 

[Hudson]

I've mentally noted not to use cheapo BBs  ̶I̶n̶ ̶t̶h̶a̶t̶ ̶g̶u̶n̶  ever again

Fixed it for you.

 

[Adolf Hamster]

tl:dr use geoffs.....

 

[RostokMcSpoons]

tl:dr use geoffs.....

I've got 18,000 Specna Core Bio BB's to get through before I can go back to Geoff's

 

[Adolf Hamster]

I've got 18,000 Specna Core Bio BB's to get through before I can go back to Geoff's

then use those

 

[RostokMcSpoons]

Ok, so part, or indeed all of the problem may have been... I'm an idiot.
I had the metal block that engages with the magazine's front lip in upside down, thus allowing a lot of extra movement that would have screwed with the feeding.

Now I've got the other common problem - the gun isn't feeding enough.

Semi-auto is fine, full auto is ok for the first shot or two, then it's only intermittently firing BBs.

I'll strip down the gun again and check the shimming to see if anything is binding inside (as per your previous comment on the 'AK not firing with all batteries' thread)

 

 

[Adolf Hamster]

Now I've got the other common problem - the gun isn't feeding enough.

Semi-auto is fine, full auto is ok for the first shot or two, then it's only intermittently firing BBs.

is this on the specna's?

because that was the exact issue (using laser dots admittedly) that started me down the path of running geoffs.

 

[Shamal]

is this on the specna's?

because that was the exact issue (using laser dots admittedly) that started me down the path of running geoffs.

So do you think it's because of the brand of BB's.?

My specna sa e-05 does pretty much the same as @RostokMcSpoonsdescribes.

I feed mine on devil blasters.

Reg

 

[RostokMcSpoons]

Yeah, on my shiny new Specna BBs.

Oh dear. 

So I tested my other guns...

In the words of Professor Denzil Dexter, "Results were disappointing"
Well, mixed.

F2000 = champ

DE M906 = champ

CA M16 = chump

AK47 = chump

The m16 went into full double-feed mode several times and i guess I've been lucky that the unjamming rod worked each time. 

I've found some split bits of BB where presumably the nozzle has chopped them in half.
I'm still getting the thing where sometimes I bang the mag in and I hear it unwind.  So I suspect the gun as much as the BBs

I've managed to shoot a hole in the bottom of my bin too... me = chump

I'll buy a bag of Geoff's to see whether the guns or the BBs are to blame.
View attachment 83450

 

[Adolf Hamster]

So do you think it's because of the brand of BB's.?

it's not necessarily the brand of bb's, but the majority of times i've seen this issue, better bb's have fixed the problem. particularly when it's binding in the magazine is the root cause.

that said, it's typically an issue you'd see more often in midcaps with a double stack single-feed, as opposed to hicaps which are single stack single feed (and as such don't bind so much)

there are other candidates, weak magazine or a pew running too fast without a delayer chip (typically manifests on auto but not semi). a longer nozzle can do it but usually that blocks everything.

 

[Shamal]

it's not necessarily the brand of bb's, there may be other issues at play, but the majority of times i've seen this issue, better bb's have fixed the problem. particularly when it's binding in the magazine is the root cause.

that said, it's typically an issue you'd see more often in midcaps with a double stack single-feed, as opposed to hicaps which are single stack single feed (and as such don't bind so much)

Good tip. I shall run it with a hicap tomorrow. Fingers crossed ? 

Regards