Newbie, Thrown Into The Luger World By Accident

[rhuff]

The "M" does not mean Mauser, it is just part of the serial number.....nothing else.

[Doubs]

Originally Posted by day late

Well, it's good for a man to know his limitations. Gunsmithing is one of mine, so I'm asking. Do you believe the problem is a weak spring under the plunger?

A weak disconnector pin spring is unlikely to cause the problem. The sear is obviously not engaging the firing pin as the action returns to battery. Considering how much rust I see, I'd be looking at the sear bar to see if it's rubbing the receiver top or bottom and staying out too far too long to catch the firing pin. The sear bar rotates on a vertical pin and either the sear bar slot or the pin - or both - may be rusted and slowing things down. Maybe the sear bar spring is too weak. The sear bar must move freely and the spring must be strong enough to move it quickly.

I'd remove the sear bar and spring and check all that out.

[spangy]

I agree with Doubs as he rarely offers bad advice and/or information.
We are lucky to have a variety of highly knowledgeable Luger aficionados here.

Although its not impossible that the Trigger Bar Plunger Pin is the problem lets not forget that Luger's went through rigorous hand fitting before they functioned as desired.

Add rust and age to this equation and ... well ... you get where I am going with this ya ??

[DonVoigt]

The "m" does not mean Mauser, it is a part of the serial number.
Lugers were numbered in series by year and started with 1-10000 no suffix, then an "a" suffix,
then "b", etc. Not an absolute but accurate for the most part.

The S/42 code is or was on top of the middle toggle link.

Your side plate, L piece, trigger, and sear bar and plunger all must work together and be fitted to each other and to the frame to work correctly. The plunger and spring would be a likely suspect, but not the only one.

You might get farther along more quickly by buying a new sear bar- if rusted/stuck the tiny spring is probably Kaput. The spring is near impossible to find by itself.

[day late]

Originally Posted by Doubs

A weak disconnector pin spring is unlikely to cause the problem. The sear is obviously not engaging the firing pin as the action returns to battery. Considering how much rust I see, I'd be looking at the sear bar to see if it's rubbing the receiver top or bottom and staying out too far too long to catch the firing pin. The sear bar rotates on a vertical pin and either the sear bar slot or the pin - or both - may be rusted and slowing things down. Maybe the sear bar spring is too weak. The sear bar must move freely and the spring must be strong enough to move it quickly.

I'd remove the sear bar and spring and check all that out.

I am using this to aid me.

https://www.americanrifleman.org/con...-luger-pistol/

You have mentioned the sear. This view of a PO8 doesn't show any part called a sear. By number, which part are you talking about?

[Doubs]

Originally Posted by day late

I am using this to aid me.

https://www.americanrifleman.org/con...-luger-pistol/

You have mentioned the sear. This view of a PO8 doesn't show any part called a sear. By number, which part are you talking about?

Items 6 through 10 comprise the sear bar assembly plus the spring. I suppose it would have been less confusing if I had used the technical terminology "trigger bar". My apologies.

If you look down the left channel inside of the receiver wall with the toggle assembly removed, you'll see the sear on the trigger bar sticking out.

While you're inspecting it, check to make sure that the sear hasn't been filed down. Also check the firing pin to see if it's been filed. While I doubt that's the case, sometimes someone tries to improve the trigger by filing those parts and goes too far.

[day late]

I know it is hard to believe, but the rust is mainly exterior. Internally, there is a spot or two, here and there, but surprisingly clean. When I have the trigger bar in my hand, the plunger moves easily. If I push it down with a finger and release, the plunger is in contact with my finger all the way up, no matter how fast I move. But my finger is different from a fired round. While cleaning this thing up, the trigger bar would always be falling out. It moves easily. I'm totally ignorant in these matters, but it does sound like a weak plunger spring to me. Assuming it is, and those things are as hard to find as I'm hearing, is there a substitute?

Edit to add, I've put about fifty rounds through this pistol while bringing it back to life. So, I've had it apart a few times. Nothing has been filed, including the firing pin.

[Doubs]

The Luger firing mechanism is really very simple. Has to be if I can understand it. LOL

A weak disconnector pin spring just doesn't seem like it could cause the problem you're experiencing. When the Luger is ready to fire, the pin is extended so that the L-arm can push it and flex the trigger bar to release the firing pin. Upon returning to battery, the pin is pushed into the trigger bar by the L-arm. That keeps the trigger bar straight and allows the sear to engage the firing pin in the cocked position. Releasing the trigger pulls the L-arm away from the pin allowing it to extend and once again lie under the L-arm, ready to be depressed to fire the pistol again. I simply don't see how a weak disconnector pin spring could cause the problem.

I can see a weak trigger bar spring - the flat spring at the back of the trigger bar - not returning the trigger bar quickly enough to engage the firing pin being a problem. Other possibilities include worn sear or firing pin engagement surfaces or too little engagement surface between the sear and firing pin to permit engagement during return to battery. But there may be sufficient engagement between the parts that lifting the toggles and returning them to battery while everything is at rest will cause it to c0ck.

If you can find someone familiar with the Luger action - G.T. for example - to troubleshoot your Luger, I'm sure a solution can be found. I can explain what the possible problems could be but unless I have it in my hands, troubleshooting it is only a guessing game.

[day late]

Originally Posted by Doubs

The Luger firing mechanism is really very simple. Has to be if I can understand it. LOL

A weak disconnector pin spring just doesn't seem like it could cause the problem you're experiencing. When the Luger is ready to fire, the pin is extended so that the L-arm can push it and flex the trigger bar to release the firing pin. Upon returning to battery, the pin is pushed into the trigger bar by the L-arm. That keeps the trigger bar straight and allows the sear to engage the firing pin in the cocked position. Releasing the trigger pulls the L-arm away from the pin allowing it to extend and once again lie under the L-arm, ready to be depressed to fire the pistol again. I simply don't see how a weak disconnector pin spring could cause the problem.

I can see a weak trigger bar spring - the flat spring at the back of the trigger bar - not returning the trigger bar quickly enough to engage the firing pin being a problem. Other possibilities include worn sear or firing pin engagement surfaces or too little engagement surface between the sear and firing pin to permit engagement during return to battery. But there may be sufficient engagement between the parts that lifting the toggles and returning them to battery while everything is at rest will cause it to c0ck.

If you can find someone familiar with the Luger action - G.T. for example - to troubleshoot your Luger, I'm sure a solution can be found. I can explain what the possible problems could be but unless I have it in my hands, troubleshooting it is only a guessing game.

I can assure you that it is not the trigger bar spring. That is one of the parts that were either missing or replaced.

[Doubs]

Originally Posted by day late

I can assure you that it is not the trigger bar spring. That is one of the parts that were either missing or replaced.

Without being able to examine the Luger hands-on, I've listed almost every possible cause of a Luger not cocking when returning to battery. There is another very unlikely possibility. The back edge of the L-arm that contacts the disconnector pin is beveled. There is enough of the edge left flat to hold the pin until the trigger is released and the L-arm is pulled away. The bevel helps the pin to release more quickly. If the bevel is too sharp and not enough flat remaining, I suppose the pin could slip under it enough to flex the trigger bar and prevent cocking. If you dry fire the pistol and continue to hold the trigger to the rear and cycle the action by hand, when you release the trigger there should be a small "click" as the pin is released.

I suppose it's possible that the trigger is depressing the L-arm enough to fire the pistol but the L-arm isn't held in far enough to engage the pin as the action returns to battery. You can check this by using layers of masking tape on the bottom of the L-arm that contact the trigger. That would push the upper L-arm farther inward and possibly cause the pin to be pushed into the trigger bar as it should be and c0ck the firing pin.

I'm fresh out of other ideas. If G.T. happens to read this thread, perhaps he knows something I've missed.

[day late]

I only have this left to offer.

[Doubs]

I see a LOT of rust. I'd begin with oil and OOOO steel wool and smooth every surface as much as possible. I'd apply oil to the toggle pins and camming surfaces and work them by hand until I was satisfied that they move freely. Remove the firing pin and do the same for it and the channel it rides in. Smooth the inside of the receiver forks if there is any rust there and the sides of the toggles.

IOW, smooth every contact surface. Just don't grind on anything. Let us know how it goes.

[Vlim]

The m does not mean Mauser.
These pistols were numbered in blocks of 10,000 with a suffix letter to distinguish between blocks.

[tomaustin]

I would add this advice----I would not put a weapon into my hands, hold it in front of my face, and proceed to fire it that has that much reconditioning to be done.....

You are proving nothing by doing this and I cannot give you kudos for exposing yourself and anyone else in the immediate area for a weapon failure.

[spangy]

I admire your tenacity, honesty and your drive to do right by this historic weapon ... the gun deserves that. I love that you haven't 'given up' on this gun, nor should you.

This is a fun project but stay focused on the goals. The #1 goal should be to not let this project spiral out of control money wise. Carefully carry on 1 step at a time, stay patient and talk to our forum members like you wisely have been.

This gun has been to war and needs rehabilitation and plenty of care ... myself I would love to own this gun just for the sheer joy of pursuing it's rebirth.

By the way I would thoroughly check the alignment both vertically and horizontally of the upper receiver forks. Even a slight misalignment here can effect the functionality of the gun.



Good luck William and welcome to The Luger World and this Forum.
Anything I can do to help just let me know OK ???

[4 Scale]

I once had a Luger that had a reset issue just like yours. Also like yours, the entire side plate assembly had been replaced. The fix was as described by Doubs in his post #30: the transfer lever had inadequate bevel where it contacted the sear plunger. After 20 minutes of work with a fine sharpening stone, it was fixed.

[day late]

I apologize for taking so long to get back. Life sometimes gets in the way. I did get some of the steel wool and working on the idea that it is easier to remove metal than put it back, I applied it gently to all of the suggested areas. I tried it and there was no change. I repeated the process and tried again. Same result. I broke down and bought another trigger bar. It arrived last Sat. A quick visual inspection shows some wear on the part of the bar that cocks the striker. It doesn't look like much, but then again it doesn't take much. The new bar has been installed, but the next chance to test fire won't be until much later in the week. I'll let you know what happens.

[Eugen]

Keep us posted on your project to save that moribund Luger. We are cheering for you.

[day late]

Got back from the range a short time ago. After replacing the trigger bar, the first mag. fired almost flawlessly. You know how it is. Fix one thing and another pops up. The safety wants to move around. More on that later. After the first mag. I started to have minor problems. One round in ten or twelve wouldn't want to come out of the chamber after being fired. I drop the mag. Open the action and get the casing out. Put the mag. back in and shoot the rest with no problem. After about the third mag. maybe one in nine or ten times, it didn't (Oh! I see spell check didn't like that word. Let me try again.) move the firing pin into position to fire. I'm hoping that the majority of this has been handled by the stirp-it-to-bare-bones cleaning I just gave it.

But now I seem to have a problem with the safety. While firing it wants to drift into the 'safe' position. You folks have helped so much up to this point, can I ask for a bit more?

[ithacaartist]

A few things come to mind.

One of mine had a similar problem with the safety lever. IIRC, a slightly larger diameter pin that holds it in fixed it.

Did you remove the lever from the frame? Others have said that crud around the lever's shaft affects its operation.

If all is otherwise OK, it's possible to remove the lever and carefully (the part is somewhat hardened, I believe.) bend/adjust the end of the lever so it presses against the frame more closely and engages the detentes more securely.