P08 Trigger Problem
 

I removed the barrel and receiver from my P08 to lubricate the slide. I reassembled the pistol after oiling and cocked it. I had to pull the trigger twice before the firing pin activated. I cocked it a few more times and the pin activated each time with one pull but the next time I cocked it I had to pull the trigger twice before the pin activated. I disassembled the barrel and receiver to check but didn't see anything out of order. Reassembled the pistol, cocked it and the pin activated. Cocked it again and had to pull the trigger twice. I tried about a half dozen more times but had to pull the trigger twice at random times. Any suggestions greatly appreciated.

Is the safety on?

Sounds like trigger bar plunger pin's issue. This plunger is the key component of Luger's disconnecting mechanism.

Agreed. The plunger at the end of the sear bar is not resetting properly after each firing sequence.

Thanks for responding so quickly. Do you mean the Sear Bar Spring when you say the plunger?

Thanks for responding so quickly. You said "trigger bar plunger pin." Do you mean the Sear Bar Spring?

Thanks for responding so quickly. The pistol won't fire at all with the safety on so I know that's working.

On the end of the sear bar at the front is a spring plunger that acts as the disconnector. When you fire the gun and it returns to battery this plunger is compressed by the trigger bar in the sideplate. When you release the trigger this plunger pops out behind the trigger bar so that it can contact it when you fire the next shot. It sounds like this plunger is not popping out when you release the trigger therefore not allowing the gun to fire. If you remove the sideplate and look at how it is linked to the trigger and sear bar you will see what im talking about.

Great. Thanks. I'll check it out later today.

W, I'd first check that you have the side plate properly inserted into the notch in the frame and that it is flush with the frame. If so, then you probably will have to do some work on the trigger lever inside the side plate, for correct resetting of the disconnector plunger. TH

Thanks for responding. Before I checked the side plate fit I put a drop of oil at the axle pin where it goes through the lever in the back of the side plate. I then carefully inserted the plate into the notch. (I took it off and replaced it a few times, checking carefully for fit.) If I hold the pistol so that I am facing the muzzle I can see a small gap between the side plate and side of the receiver. I can slide 3 thicknesses of regular bond paper edgewise into the gap (about 1/64). I can press the side plate snugly to the receiver but it doesn't stay there. Pressing the side plate before pulling the trigger doesn't help. I then cocked and pulled the trigger very slowly. Feels like something is not operating smoothly, like an obstruction then fires. Unfortunately when I cocked it again I had to pull the trigger 3 times before it fired.

Did you check the plunger on the sear bar to see if it is indeed sticking in and popping out slowly?

Yes I checked that. It works fine with the trigger side plate off but it's covered when I replace the side plate so I can't see the action. I put a drop of oil on and worked the plunger quite a few times before replacing the side plate but that didn't help.

Seems very odd. If you have the gun cocked with it assembled then remove the upper will it release the firing pin when pressure is applied to the sear bar? If not I would say the issue is with the sear bar or firing pin. If it does release I would think the problem is in the trigger/sideplate/sear bar engagement. That would be an area where I wouldnt know what to do.

I agree it's odd. The pistol has been handled carefully. Just took it out for a periodic wipe down and ran into a brick wall. Could you please explain what you mean by "remove the upper." What part are you referring to? (I looked at the P08 disassemble video and noticed that when the demonstrator pulls the toggle back to **** the pistol the toggle stays up by itself. I have 3 P08s and the toggle doesn't stay up on any of them.)

You very likely have 3 p08's like my p08 which does not have a last shot hold open. What I mean is make sure it is cocked, then remove the sideplate and slide the upper assembly (barrel,receiver,toggle assembly) off the front of the frame. Now push on the sear bar toward the barrel end and see if it releases the firing pin. If so I think you have an issue with your sideplate. If it doest release I'd say the issue is with the sear bar or firing pin.

I followed your directions. The sear bar doesn't move and the firing pin is not released. The plunger located in the front of the sear bar pushes back easily. It springs forward into position when I release it. I reassembled the barrel, receiver and toggle assembly and pulled the trigger. I then disassembled the same parts and tried to push the sear bar. It won't move in either direction. (I have a parts map with labels so I can be sure I'm identifying the correct parts.) Should I be able to move the bar? Do you still think it's the sear bar or firing pin?

I played around a bit more then realized the sear bar actually pushes inward, not forward. I went through the process you described and the gun fired. If I understand correctly you suspect it's the side plate if the pin fires.

Hmm... when pushing the sear bar you should be pushing the front half of it towards the other side of the gun. Such as put your thumbnail on the side of the plunger and push it in towards the center of the receiver. If thats what you did and it wont release it sounds like something is binding.

Walt,

When everything is assembled, is there play in the trigger plate fit against the side of the receiver? Does the take down lever hold it close to the receiver without movement? Earlier you described a 1/64 inch gap. Is that where it is? Is it flat and parallel against the side of the receiver, or at an angle?

Look inside the trigger plate and look for dirt behind the trigger bar (a right angle transfer bar). Make sure that the small pin is holding it square with the trigger plate.

This area was hand fit by the factory for each Luger. That's the reason the parts were numbered to the pistol s/n. Is your Luger matching?

The right angle transfer bar is hardened, and will snap if you try and bend or "re-form" it. Not something to do yourself.

Marc

Yes I pushed the bar the way you described and the firing pin released. I noticed the spring on the back of the trigger is compressed so I took the trigger and side plate from a pistol that works fine and installed it on the faulty pistol and the same problem happens. Doesn't that eliminate the side plate and trigger?

I checked the gap against a pistol that works fine and they are the same, a bit less than 1/64th. I noticed the spring on the back of the trigger is compressed so I took the trigger and side plate from a pistol that works fine and installed it on the faulty pistol and the same problem happens. Doesn't that eliminate the side plate and trigger?

Im not sure but it seems strange. Hopefully one of the experts can help you. Does the gun your having trouble with have matching #'s on the sideplate if not that could be your problem.

The pistol doesn't have matching numbers but I've had for 4 years and never had this problem. I realize it's an old pistol but everything worked fine until I took it out the other day. One of life's great Luger mysteries? I plan to field strip and clean it then see what happens.

Not necessarily. The "L" shaped transfer bar inside the sideplate may not be extending far enough to really gain a purchase on the sear bar. Since bending this lever is very tricky, (it is hardened and will snap if you try to bend it). A method you might try is to apply a tiny strip of electrical tape on the tip of the lever which engages the sear bar, (do this once the pistol is cocked, remove the sideplate while holding upper in place, apply tape, then replace sideplate directly over the cocked sear bar. You want to do this because the tape will interfere with the lever's travel over the sear bar if you try to **** the pistol with the tape in place). If the pistol then dry fires with less effort, (you should be doing this with a snap cap in place), then the original lever has not been engaging the sear properly.
Some members have laughed, but I have solved this problem by building up the upper pad of the L transfer bar by applying JB Weld. I then file it down until I achieve the proper sear engagement, keeping in mind to radius a "ramp" on the pad edge farthest from the muzzle, so that the sear bar plunger can properly ride over the L link.

This is obviously more easely explained visually, but I hope you get this.

With the pistol cocked and UNLOADED

1. Hold pistol with right hand
2. Put the muzzle against your left hand. Push the upper back against spring pressure unfilled it stops.
3. Pull the trigger and release the spring pressure.
4. Slowly release the trigger.

You should hear a click when the sear plunger releases. If you don't hear a click, the plunger is not resetting.

If it is not, you should check with Luger Doc.

Followed your suggestion and didn't hear a click. Can you please tell me what or who Luger Doc is?

Post #10 in this thread Tom Heller he is the Luger Doc

Have followed everyone's suggestion without success. The last suggestion was to push the muzzle back, press and hold the trigger, release the barrel then slowly pull the trigger and I should hear a click. I tried a couple of times didn't hear a click. I took the side plate from my other Luger that works fine and installed it on the problem pistol. The problem was still there. You mentioned I would have to do some work on the trigger lever inside the side plate. What do you suggest? I looked at the side plate of my working pistol and the action, how far the lever moves, etc. looks identical.

You should hear the click when you release the trigger it is the sound of the sear bar plunger resetting.

You should hear the click when you (release) the trigger. It is the sound of the sear bar plunger resetting. If the plunger moves freely with the gun apart, but doesnt reset with it together it sounds like the lever on the sideplate is the issue. But I really couldnt tell you.

If I hold the pistol so that I am facing the muzzle I can see a small gap between the side plate and side of the receiver. I can slide 3 thicknesses of regular bond paper edgewise into the gap (about 1/64). I can press the side plate snugly to the receiver but it doesn't stay there.

It could be possible that your locking lever has been bent outward not allowing it to press against the sideplate flange.

Good Point. I hope to figure something out now that I have all the input from you guys. I learned a lot today and thank you for it.

Walt, If your luger is a mismatch shooter, probably the easiest fix would be either a different FP or sear with less overlap between them. It's also possible that some judicious bending of the side plate arm could improve things. Finally, if all else fails, replacement of the trigger lever in the side plate or heating & bending, so that the disconnecting pluger in the trigger bar can push it more easily out of the way to recock, would be the last resort. TH

Thanks again for the advice. I'll clean it up first and see what I can do.

I'll throw in with Tom Heller's suggestions/observations here. Here's another thing to check, to see if the side plate is held rigid by the takedown lever: Unloaded gun, of course, hold your finger on the juncture line of the frame and the rear edge of the sideplate, where its lip tucks under the frame. Flex the trigger and you will be able to detect any rocking/movement displayed by the sideplate when the trigger is pulled; you'd be feeling the sideplate's movement relative to the frame. As Tom mentioned, it's possible to tighten this up by careful bending of the sideplate's arm, which is what is clamped firmly by rotating the takedown lever over it. I recommend you spend the best $7.95 ever, for a copy of Gerard Henrotin's e-book Luger Function at http://www.hlebooks.com/ . If you read the pertinent chapter, you'll understand the parts and functioning of the trigger system, which would be good. It might help to check that the trigger spring, behind the trigger, is robust and functional and not wimped out by age and use, to be sure that the trigger itself is returning to proper position and not causing the bar in the sideplate to return to where it should.

I'm thinking the sideplate may be loose enough that its bar can't consistently escape its interaction with the sear's plunger, and might still hang up on the plunger's tip even though the trigger is released. If it were hanging up this way, flexing the trigger would only cause the tip of the bar to scrub across the face of the plunger's tip, not letting it pop out, so that the bar would be unable to press the plunger's side, as needed to rock the sear and release the fp. Jiggling it back to its full rest position--or at least the point where the lever's end allows the plunger to pop out again--may be what is accomplished by the repeated trigger pulls. The mechanical system may have right been on the edge of proper function all along, then pushed erratically across that line by use and continuing development of play within the system.

Ultimately, there can be no "mysteries" within a mechanical system. Its operation is all according to the laws of physics and mechanical interaction. If the mechanics are complicated, as are those within our beloved Lugers, this increases the number of variables geometrically because of the exponential growth of the number of different combinations of parts' interactions involved. Be patient... we'll get you through this if we can..and Lugerdoc is the ultimate backup resource!

David Parker

Puzzling? Just a thought. Check the FP and the inside of the sear bar for any burring... Also is the trigger spring original, and fitting correctly?

FN

I have had the same problem with my brother's shooter. I realized after screwing around with the trigger lever that the problem was a very loose takedown lever, and not enough pressure on the sideplate . I carefully bent the takedown lever so that it locked the sideplate much more snuggly, and that seemed to work. I used a vise and pliers with adequate protection for the metal.

P08 Trigger Problem
 

By take down lever, do you mean the locking bolt? I've attached a parts map. The locking bolt is number 025.

Thank you for the excellent advice.