Gah, what i think is an airseal issue, BB's falling out the end of the barrel
 

Well, over the last few days i have made a few posts here, I opened up my mechbox for the very first time...and i am having some issues! My mechbox seems to be mostly functioning properly, except for a glitch with what I believe to be the gear timing. when firing in semi auto, the mechbox firing, but the piston returns to the fully cocked piston. this will soon kill my spring, I was given a very detailed answer that i think will solve my problem, but after re-disassembling the gun and giving it a few test shots, i ran into some issues.

When the trigger is pulled, i can hear the mechbox fire ( i can see it firing if i remove the magwell) but the BB does not leave the barrel, if i tilt the gun downwards it will fall out the barrel. I have tried adjusting my hop up with no luck. Any ideas??

It is a JG G36c
mostly stock slightly weaker then stock spring and sorbo
I have a M4 magwell and the standard magwell, i have tried both ,and both give the same results...

I'm assuming its some sort of air leak, but i really don't know enought about this sort of thing to know for sure.

I did my best to look for a thread, or something on google that would solve this issue, sorry if it is a repost.
any help would be greatly appreciated
Thanks in advance
-Ben

It almost seems as if your gun isnt timed properly.


Check out mechbox.com
That site saved me hours of bull. Very detailed video about taking apart, puting back together, your mechbox

done that, many a time, I have the tappet notch set to 1 o'clock...

in facts, gear timing doesn't really exists as the gun auto time itselfs on semi.

For the bbs, I'd suggest you to use silicone oil in all the cylinder area and even in the hopup. Also, check if the cylinder is placed in the front of the gearbox and the oring between the cylinder and the cylinder head is not dry.

-Hop up unit mis aligned with the magazine
-hop up unit and the mechbox misaligned
-Misaligned installation of Hop up rubber
-Poor installation of hop up rubber(hard to explain)

it probably has nothign to do with the mechbox interior, there's just some kind of problem among the positioning of mechbox-hop up unit - magwell - magazine

haven't toughed the hop up, its still all stock, maybe i nudged it out of place by accident...

Possibility of not enough hop?
My MP5 was having the same issue and then I just dialed in a little more hop and it solved the problem.

You might have disconnected the nozzle from the tappet plate.

Also...NEVER look down into the hopup feed tube while firing the rifle, unless you are wearing protective goggles and have your mouth closed...if there is a jam and there is a bb in the feed tube...where do you think the air is going to push the bb out?

I opened it up first time too, checked and did everything, noticed I forgot to connect the nozzle to the plate. hah! A little 1 second connection took me over 32 hours to figure out the problem.

Hmm... i think the air nozzle is connected, it still moves in and out if i fire the mechbox when its out the the body.

I think i have another symptom, when i fire the gun loaded and all assembled, some bb's fall out the end, but when i remove the mechbox, and slide down the cleaning rod several BB's are stuck in the barrel, i have thoroughly cleaned it...twice

Say... what kind of BBs are you using?

KSC perfect .20's

Can someone explain how i could check this? I know nothing about hop up units...

I believe we have the same problem!

There is a spring that pushes the hop up/barrel towards the gearbox, but is stopped by some piece. My piece broke off(probably not your problem). This piece stops the hop-up from getting too close to the gearbox. If it's broken(small piece), this stops the feeding from the magazine. There is not enough room for the bb to enter the barrel. This happened to me, so I took off the spring from the barrel. You align the hop up properly with the mag, and voila! But after like maybe 20 bbs, the barrel slips fowards and the entry space into the hop up becomes too big, causing an air leak(probably your problem). The bbs either go into the barrel but don't have enough power to get through, or just don't go into the barrel.

Well, hope I helped. I tried to find a way to immobilize the barrel when it's in the correct position. But I still can figure out how to do so without having it permanently in place.

Good luck. If you have other questions pm me. Might not help, but whats to lose?