G&P Firing issues

[Devinian]

Its there. Ill give that a shot after work. Im probably going to take the mechbox apart and check that i didnt break anything. Are shims important cuse im perdy sure i lost a few in the many time iv taken it apart.

[CDN_Stalker]

Shims are very important as they have to prevent the gears from moving side to side and coming out of alignment, as well as to (when properly set) give maximum meshing between the gears for a more spread outload bearing.

Shims aren't your current problem though, your hop up unit shouldn't move back and forth freely, if you can move it forward it should spring back. If it doesn't, your spring isn't doing it's job and chances are is a main cause of the problem.

[Flatlander]

Stalker's right. Having the spring push back against the mechbox is very important. One gun I worked on the barrel assembly wasn't aligning right causing the inner barrel and hopup to stick inside the outter barrel, not allowing the hopup to push back against the mechbox. Fixed that problem and got a nice 'bounce' with the hopup and it immediately jumped up 100fps. It will also drastically help with the fps consistency.

[Capt. T/O]

my g&p had similar problems.
pm nova316 here on asc or on JOC (same board name)
he will get it straightened out for you.
my g&p is running fine now.

Originally Posted by Devinian

ok update time.

I noticed that the nozzle was infact visible when the gun should be loading, when i pulled on the hopup unit it was able to move back and forth so I put a O ring on the black one pice hopup, where it connects to the mechbox. this stoped the movement and the nozzle wasnt visible anymore.

the gun accually worked for almost one mag. It didnt have enough power to break through one side of a pop can. and eventually just started getting jammed. Im assuming that it dosnt have enough power to push the bbs through the hopup unit because i could push them through with a pen.

I removed the oring and tryed firing it and, yup it didnt work, just jams up. so i put a o ring on the other side of the hop up unit. ( slid it on the barrel) this also tightened it up against the gearbox. but it didnt seem to improve the situation.

Im totally lost now. Any Repairmen in calgary? I think i need a professionaly to take a look at it.

[m102404]

Originally Posted by Devinian

ok update time.

I noticed that the nozzle was infact visible when the gun should be loading, when i pulled on the hopup unit it was able to move back and forth so I put a O ring on the black one pice hopup, where it connects to the mechbox. this stoped the movement and the nozzle wasnt visible anymore.

the gun accually worked for almost one mag. It didnt have enough power to break through one side of a pop can. and eventually just started getting jammed. Im assuming that it dosnt have enough power to push the bbs through the hopup unit because i could push them through with a pen.

I removed the oring and tryed firing it and, yup it didnt work, just jams up. so i put a o ring on the other side of the hop up unit. ( slid it on the barrel) this also tightened it up against the gearbox. but it didnt seem to improve the situation.

Im totally lost now. Any Repairmen in calgary? I think i need a professionaly to take a look at it.

I was surprised when the o-ring DID NOT produce an air leak, it should have...I was more troubleshooting the misfeeding problem rather than testing FPS, it was just a nice bonus in my case. It was a lot easier to use an o-ring than to disassemble the rifle and/or crack open the mechbox.

Putting an o-ring on the other end will do nothing to help and just exacerbate the problem.

Just thought of this last night...but has anyone found "stuff" on the rear of the lower receiver, where the back of the mechbox would butt up against the buffer tube? One receiver has what looked like really thin foam rubber tape and the other just had a bunch of paint build up. A body with stuff in the rear of the lower could "push" the mechbox too far forward.

Anyways, best of luck!

[Nova316]

Heya, I just ended up trouble shooting his gun, It does have an airleak... Theres an airleak between the cylinder head and the Nozzle.. the Oring inside the nozzle was completely torn, to the point where it came out in 3 pieces. So that needed to be replaced with a polycarbonate one

The hopup was another problem.. the bucking was a hard piece of plastic looked like it was cut out of a piece of straw.. I replaced it with a piece of 16ga silicone wire.

Now into the mechbox.. It has literally.. 2 shims on all the gears combined.
and the spring is maybe a M120 it shoots about 375..

Just gotta shim it and test it, Thats all I found wrong so far

[mcguyver]

Originally Posted by Nova316

The hopup was another problem.. the bucking was a hard piece of plastic looked like it was cut out of a piece of straw.. I replaced it with a piece of 16ga silicone wire.

That gun didn't come from up north by any chance? I know a guy who used to repair them that did that. The plastic he used was from the refill of a Bic pen or similar. They worked, but would wear on the hop rubber like you wouldn't believe.

[Nova316]

Im not sure where it came from, Ill have to ask him..
It was very sharp, it does look like its from a bic pen.. but its not even close to the right dimension It did work but only some of the time, it had different pressure across the entire bucking, sometimes the bb would get stuck sometimes there would have backspin and other time the bb would just roll out of the barrel

Just got it up and running, took me 2 and 1/2 hours to trouble shoot everything. Fires perfectly now

[Devinian]

Thanks alot everybody, I really appreciate you help.
I havent tested it personally but I think its resolved.

Lorant

[Devinian]

ok update time.

The gun is shooting consitently in single with a tight fps of 380, it is misfiring every second shot in full auto. Iv ordered a sector chip and waiting for it to arrive, Thinking back to 2006/2007 this gun has always had issues with its full auto, so maybe all it needed is a sector chip. I had two hopup units one with a soft rubber piece and one with a hard plastic piece, not too sure where i aquired my black one from but im sure it was free.

Also I did some maintenance on my mags to insure they wernt being a problem.