Luger slam fire Question

[bzh362]

I inherited a p08 luger a while back. It's a mixed serial number gun, and I suspect that at least certain parts were re-blued, so not much of a collector's piece, but still super cool. The barrel was in really rough shape. I test fired it a bit (a box worth of ammo), but the brass was coming out a bit bulged pretty marked up from the rough chamber.

Long story short, I sent the gun off to get a new barrel put on. When I got it back, I of course went to the range to see how it shot. I put two mags through it, and then on the third mag, when I released the toggle, the gun discharged! Not a big deal since I was pointed downrange at the target, but still not a good surprise.

Any Luger experts out there who could provide me with a bit of insight into what might be happening? When I got home, I stripped the gun, and looked for wear in the sear / trigger area, but did not see anything that looked unusual to me. The sear spring was did not feel particularly weak, but I'm not too experienced with this platform.

Thanks in advance Calguns!

[hermosabeach]

I would call the Smith that did the rebarrel as they are versed with lugers....

[bzh362]

I actually did not have the best experience with the smith, and although the work seems to be good, I am reluctant to contact him again.

[phsieh10]

might want to check the side plate. The transfer bar may be bent. Or could be a sticky firing pin. You might want to clean it.

[bzh362]

I checked the side plate, it does not appear bent, and is at 90 degrees. I cleaned the gun when I got it back from the smith, did a full disassembly of the upper.

[kcstott]

I checked the side plate, it does not appear bent, and is at 90 degrees. I cleaned the gun when I got it back from the smith, did a full disassembly of the upper action/toggle.

Fixed that for you. It's Not an AR

[ThePatriot]

I have 8 Lugers (PO8's) and have not run into that particular problem but it seems like you should start at the firing pin and work backwards since the pin must be forward for it to fire. This does not sound like a headspace problem. Get some A-Zoom or similar dummy rounds and manually work the toggle to chamber a round, if there is a lack of headspace the toggle will not go all the way down. With a dummy round chambered slowly pull the trigger and make sure that you hear a nice click, do not release the trigger. Then, still holding the trigger, work the toggle again, chambering the next dummy round. Slowly release the trigger and listen for the click as the trigger resets. Pay attention to any grinding or sticking. Try chambering a round again with your finger off the trigger the whole time and then pull the trigger to make sure it set, if there is no audible click then you have a reset issue. In order to eliminate the trigger and trigger plates as a potential problem take the slide off of the gun and work the toggle to cock the firing pin. Lugers can be loaded and shot without the frame attached, lots of German police found this out the hard way. To release the pin push in on the front end of the sear bar and you should hear it click. Try several times, resetting and releasing to make sure it clicks each time. If during this testing process you fail to hear a reset or firing pin drop then you know that there is a mechanical issue. I have one Luger that is a bit touchy and will bump fire if there is much pressure on the trigger as the toggle cycles, might be you were touching the trigger and did not realize it. The only other thing I can think of is that your sear bar is worn and it did not catch the pin as it comes forward. You might try and see if it will chamber a round and come forward without the toggle being pulled all the way back. Sear bars are not hard to find and it seems to me that if it was a true slam fire then this is the most likely culprit. Changing your trigger spring would be my second thought and is always a good idea if you have a sticky trigger reset.

[phsieh10]

Did you remove the firing pin and clean the recess and the pin. Your firing pin could be stuck or the spring could be broken. It coul also be your sear or sear spring. Since the sear and sear spring are part of the upper frame. The smith may have put too much clamping force on the frame when he removed the barrel. Also, when you released the toggle on the third mag, did you accidentally press the sear. The Luger has an exposed sear. You can actually fire the pistol without touching the trigger.

Picture of toggle with firing pin removed


Picture of sear on upper frame

[ThePatriot]

Did you remove the firing pin and clean the recess and the pin. Your firing pin could be stuck or the spring could be broken. It coul also be your sear or sear spring. Since the sear and sear spring are part of the upper frame. The smith may have put too much clamping force on the frame when he removed the barrel. Also, when you released the toggle on the third mag, did you accidentally press the sear. The Luger has an exposed sear. You can actually fire the pistol without touching the trigger.

Picture of toggle with firing pin removed


Picture of sear on upper frame

Exactly right. I supposed the sear engagement surface on the side of the firing pin might be worn as well, causing it to slip.

[phsieh10]

I guess I should have taken a picture of the sear from the inside. Just never carry a Luger chambered on safe. You can't rely on it.

[bzh362]

Yes, I took the toggle assembly all the way down to clean and lightly oil the firing pin. It is possible that I hit the sear, but I doubt it as my index finger was on the right side of the gun, and my thumb was on the wood portion of the grip (I know because I felt the checkering bite when it went off).

The trigger resets fine, but I noticed the trigger didn't exactly spring forward. I am going to look into replacing the trigger spring to see if that helps.

Thanks for all the input! We'll see how it goes, and I'll update after the next range test.