Trigger gate on mg34

[zb37]

My trigger gate is too wide to go in the slot in the bolt. The sear is too low for the trigger gate to trip. What is the problem?

[DARIVS ARCHITECTVS]

Please post clear close up pictures so the MG-34 collectors can help you. We can't help if we don't have enough information. Thanks!

[JBaum]

I'd guess the first problem is that we don't know what a trigger gate is. Second would be what the sear is.

Here is a picture with all the parts named. Try it again, using the names in the pictures, or give us some pictures of your own please.

C1 Grip
C2 Trigger Rod
C3 Trigger
C4 Trigger Detent
C5 Coil Spring for Trigger Detent
C6 Rivet Pin for Trigger Detent
C7 Coil Spring for Trigger
C8 Spring Head
C9 Disconnector
C10 Coil Spring for Disconnector
C11 Rivet Pin for Disconnector
C12 Detent Hook
C14 Rivet Pin for Detent Hook
C15 Coil Spring for Detent Hook
C16 Down Pusher
C22 Grip Plate, right
C23 Grip Plate, Left
C24 Holding Screw, shorter
C25 Holding Screw, Longer
C28 Split Bushing
C29 Split Pin
C26/27 Rivet Screw

[anjongni]

I believe the discussion involves the TNW semi-auto MG34 system. The trigger gate is a spring-loaded blade that trips their firing lever.
Mine is too wide to fit in the bolt slot too. It just barely touches the firing lever, but if you pull the trigger hard enough, it works. Chris P Cook has longer trigger levers, that might alleviate the problem. Not a super design.....
Are you using a re-weld or a TNW receiver? Are you trying to use TNW's super-strong FP spring? I believe the original FP spring works just fine. You might put that in and try it. Please let us know if you discover the secret!

[ChrisPCook]

As mentioned, need more info....original TNW or Reweld? If this is a reweld that you have done the trigger gate area on the TNW is substantially different than the original 34...needs to be altered to properly accept the trigger gate.... Chris...

[zb37]

I am using a reweld done by Pirate. The trigger gate seems to come up far enough, but the sear doesn't seem to come up far enought. Seems to me the sear trip needs to be up higher. No matter how hard I pull the trigger, it will not trip the sear.

[ChrisPCook]

I've only had a problem w/ length....if it's too wide to fit in the bolt slot how much do you need to thin on each side of the trigger gate half moon? If that is the problem? One other thought might be to get a spring with fewer coils for the trigger gate??? Perhaps the spring is bottoming out not letting the half moon on the trigger gate to come all the way up into the sear? Chris...

[zb37]

It would take quite a bit of thining to make it fit the bolt slot. I am thinking that this is the way it is supposed to work. Sear trip is not high enough for the trigger gate to engage and trip the sear. Trigger gate appears to be comming up far enough, but unless in would go into the bolt slot, I don't see how it would ever work.

[anjongni]

Hi zb37, a couple questions: Did TNW do all the machine work on your bolt? They machine almost all the parts, the bolt head, carrier, holder with the two pins, and the retainer. They also weld up the original firing lever and change the ejector. Do you have all the TNW parts assembled correctly with the hardened sear ring and little snap ring? If it will cock and fire in your palm, with a pliers, and the original WW2 firing pin spring, you're almost there.
I don't think that the trigger gate is supposed to fit into the slot in the carrier. If it were too high, the bolt would peel it off upon recoil. When it's assembled and cocked, the trigger arm sticks down far enough for the trigger gate to trip it, if all the dimensions are correct. Good luck....Phil

[zb37]

All the parts are TNW. I machined the bolt and installed the parts. Will fire with pliers, but not with the trigger gate. Sear ring and clip spring installed correctly. All machine work was in spec with instructions.

[anjongni]

Hi zb, will try to show some pictures of my TNW bolt, cocked. The trigger gate accesses the firing arm by way of two reliefs that you machine in the back of the bolt carrier. The trigger gate doesn't actually enter the slot in the bolt carrier; it's much too wide. I have the TNW machining dimension instructions if you need them. Mine works acceptably, if stiffly. Good luck...Phil

[junglewalk]

Below is a photo of an early totally done TNW bolt....Of course, it is the underside of the rear, for you guys that don't have one of these.
..,,,You can clearly see the sloped/beveled edges of the end of the slot that is cut in the bolt carrier.....Without this cut beveled area, the hinged & spring loaded 'gate' coming up from the trigger group, can not push the see-saw like trip on the bolt to allow the firing pin to fire.
......Is your bolt carrier rear underside cut in this way?....bh

[junglewalk]

Ha!.....6 minutes apart when we posted pics!............ha

.....

[anjongni]

Wow, what do they say about great minds....! Jungle, from your photo, looks as if, if the bolt head failed to cam completely into the barrel thread, the bolt carrier would "shroud" the firing pin lever to prevent its being tripped by the trigger gate. Perhaps to prevent an out-of-battery incident. I can see where a longer trip lever might work better here, with more leverage, or a longer relief cut into the bolt carrier, yet possibly not be as safe. Interesting, hope this helped zb37.....Phil

[zb37]

Yes this helps tremendously. Never saw this before. Instructions they sent never mentioned this. Now this makes sense. Thanks for the help. I believe that I can make it work now. Thanks again.

[Swiss]

OK, the suspense is killing me...did you get your trigger system to work?
I purchased a half-way finished MG34 with a Pirate re-weld. I have yet to get my trigger to fully engage the \trip lever and hence, no release of the firing pin. It seems that the travel of the trigger is insufficient(?)

[ChrisPCook]

Is the half moon on the trigger gate making movement into the bolt trip sear?
Is the recess for the trigger gate hollowed out far enough to the rear to allow a full upward movement of the trip arm?
Is the spring under the trigger gate able to fully compress to allow upward movement of the trigger gate arm?

Just a few things to check right off the bat.
Also, if the receiver length is even slightly out of spec it may not be able to engage trip sear on the bolt, that's why I made my longer trip arms to correct the difference.....good luck, Chris....

[zb37]

The trip lever is a tad short. I think I took off too much material on the bolt body. The trigger gate makes contact, but slips off the back of the trip lever. I have another bolt body without rollers. Not sure how to take these off the old one and put on the new one. Maybe someone could help with this.

[zb37]

I believe a longer trip lever would work. Do you still sell these. I miked everything and thought everything was in spec. You are probably right about the receiver being a tad out of speck.

[ChrisPCook]

I have some left, I'll shoot you a PM....