WE G39C - Not Firing

[Bar1975]

Got a buddies WE G39C GBBR that does not shoot.

The charging handle can be pulled back and when you pull the trigger you can hear a click but nothing happens.. there is no gas release of any kind. (like there is no mag in the gun at all)

I looked into it and found that the gun had a broken Firing PIN. The part that the hammer hits was snapped off.. so that's the problem or so i thought.

I just installed a new RA-TECH Firing Pin and now i can visibly see a pin popping out of the mag well when i pull the trigger but the same thing is happening!!

I am wondering if the pin is still not hitting the magazine valve? I only have the one magazine so i can't tell if that is the problem or not..

If when the trigger is pulled and the firing pin pops out from the trigger box there 'should' be nothing else that is wrong with the trigger assembly right? This pretty much has to be a magazine issue?

Is there any way i can mod the pin to push out even more than it is now?

[siggypoo]

It sounds like you've diagnosed the problem correctly. Save yourself a bit of extra diagnostic heartache, and remove the lower receiver from the upper. The lower receiver is the grip, trigger group, and magazine well. Can you see the "firing pin" (actually called a "valve knocker") striking the output valve on the empty magazine when the magazine is inserted? Does the valve knocker travel freely within its slot? Gently press the back of the hammer with your thumb and watch if the hammer connects properly with the valve knocker, and if the valve knocker depresses properly.
If all that goes well, then my uneducated guess is that your replacement valve knocker is 5x5 and doesn't need any editing on your part.
All that tells me, is that you could likely divert your affections elsewhere. How's the output valve? Clean? Dirty? Stiff to press when ungassed, or easy to depress?
I hope I don't get flamed for my ignorant troubleshooting hints, lol. I really don't pretend to know your issue either. Best wishes for a quick fix for you though.

[Bar1975]

i replaced the firing pin only.. i didn't replace the valve locker. The RA Tech set came with both a pin and valve locker. I am wondering if they both need to be installed together?

The one thing i did check for was the pin moving in and out of the receiver.. when the hammer is back the pin is back.. when the hammer is forward the pin extrudes out of the trigger box and into the mag well.

I'll double check now with the mag in and the lower removed to see where it's hitting the mag.

The mag in general is easy to depress when not gassed but the valve pin seems recessed a little inside the mag... i dont belive the firing pin is even hitting it.

[siggypoo]

Oh, sorry. I didn't know the pin and knocker were two separate parts. My G39C only seemed to have one. Maybe you're right and the two Ra Tech parts are best installed together.

[Kos-Mos]

Remove the lower as suggested above.

Release the hammer, and watch carefully as the you pull it back. You want to see if the strike pin (valve pin) move at any point before the hammer is at the rear.

If it follows the hammer, you need the locker, yours is snapped in half.

Also make sure that the valve pin is retracted when you insert your mag. Happened on my SCAR with the RATech pin. If I dropped the hammer on an empty receiver, the pin would not always retract when I cock the gun. Then when the mag is inserted, the pin moves up (It's made for that), but does not fire. All it does is "tock", like there is no mag.

I that happens, cock the gun slowly while pushing the strike pin. It's going to jump back. In my case the new part worn in place after a while. It also does not do it if the striker is retracted when mag is inserted.

[Bar1975]

Originally Posted by Kos-Mos

Remove the lower as suggested above.

Release the hammer, and watch carefully as the you pull it back. You want to see if the strike pin (valve pin) move at any point before the hammer is at the rear.

If it follows the hammer, you need the locker, yours is snapped in half.

Also make sure that the valve pin is retracted when you insert your mag. Happened on my SCAR with the RATech pin. If I dropped the hammer on an empty receiver, the pin would not always retract when I cock the gun. Then when the mag is inserted, the pin moves up (It's made for that), but does not fire. All it does is "tock", like there is no mag.

I that happens, cock the gun slowly while pushing the strike pin. It's going to jump back. In my case the new part worn in place after a while. It also does not do it if the striker is retracted when mag is inserted.

I've personally taken apart the trigger assembly and can confirm nothing is snapped or broken.

The gun is firing now but seems to be a little inconsistent.. i think it maybe the body tolerances warped/bent a little and not positioning the mag properly all the time.. who knows.

So as a general rule the bolt should be back(causing the hammer/pin to be back) when inserting a mag.. even the first mag? (It's back naturally when the mag empties because of the bolt lock)

[Kos-Mos]

Originally Posted by Bar1975

I've personally taken apart the trigger assembly and can confirm nothing is snapped or broken.

The gun is firing now but seems to be a little inconsistent.. i think it maybe the body tolerances warped/bent a little and not positioning the mag properly all the time.. who knows.

So as a general rule the bolt should be back(causing the hammer/pin to be back) when inserting a mag.. even the first mag? (It's back naturally when the mag empties because of the bolt lock)

Yes, well no.

G36s don't need the bolt to be at the rear (real ones).
All WE GBBR also don't need that (it's good practice however since you can break your nozzle if your mag is too full).

But I had this issue with the RATech valve knocker. It is just too tight in the trigger housing and binds extended sometimes. Under normal operation, the mag valve spring is enough to push it back.

It will get better over time, or you can file/polish the trigger housing.

[siggypoo]

So all we're troubleshooting here could be attributed to normal wear-in (breaking-in)?

[Kos-Mos]

Originally Posted by siggypoo

So all we're troubleshooting here could be attributed to normal wear-in (breaking-in)?

The "replacing parts not fixing" yes.

RAtech parts are not exactly to spec, and I found most of the time they need to be worn-in to work properly.