1942 Luger Issue
 

I have a 1942 4" Mauser Luger. I was told to come to this forum to ask for advice.

Sometimes when I fire the luger, the toggle lock does not go down all the way. I have to touch it and then it will lock down. Any ideas? My gut is telling me its the mainspring. It does it on the original mag and two mecgar mags, so I dont think its a mag issue.

I was using 124gr 9mm ammo

Thorough cleaning and generous lubrication come to mind as a place to start. Also it is critical to firmly grip the gun when firing so that the effects of recoil can do their job in the process.
Also check to see it any parts of the (EMPTY!) magazine are dragging as the bolt moves forward. Does it snap closed easier with no mag?
Try those and we can go from there.
dju

What brand of ammo? Factory or reloads?
dju

Perhaps you should tell us what you think is the "toggle lock". An M1900 Luger has a toggle lock, but a 1942 Mauser Luger would not.

Pics, taken by a friend next to you while this happens, would help explain the problem more clearly. :)

First, ensure that you're using brass cased ammunition.

Take a look at the back of the receiver between the ears where the toggle train rear piece hinges and it touches the rear surface when fully in recoil. Is it leaving any marks there?

The recoil spring on a late Mauser made Luger should have 19 to 21 coils.

Check all the toggle action to ensure it's clean and lubricated with light oil.

Check the inside surface of the chamber to ensure it's clean and shiny. Any pitting there would be a possible issue.

Ensure you are supporting the pistol properly when shooting. It does have a great deal of impact on proper cycling.

Double check the OAL of the ammunition. Try cycling a round in, and then remove the round intact without shooting it. Are there any marks where the rifling starts along side the bullet surface?

Marc

Magazine is not dragging. Ive cleaned the gun, bore brushed
The chamber and oiled the toggle, bolt area, slide rails.

On my luger if you pull the gun back 7/8" or so, the striker cocks and if I let go, the toggle will stay up slighlty (without a mag inserted).

My failures to go into battery duplicate this position.

The gun is head tightly when fired. The failure happen about 10% of the time.

I will count the spring coils when I get home from work

The oal cartrige should be fine, but Ill check when I get home. The ammo Im using fires fine in a hi-power and P-38

Although it fires fine in the other guns, be suspect of it in the P08.
Factory or reloads, brand, FMJ?
It's just part of the process of elimination.
My Hi-Powers and P-38's will eat absolutely anything, whereas the Lugers will not.
dju

This is normal for the toggle to not return to battery if raised enough to c**k the striker and then released. If you are using quality ammo...i.e. WWB, PMC, S and B, etc. then that helps us a lot, although many lugers are ammo sensitive.

I am beginning to focus in on a tired mainspring. Have you, or anyone else ever changed it? springs do lose their strength over time.

If you are trying to shoot reloads in your Luger, stop that for right now, and use only good quality factory 115/124gr RN FMJ ammo. Use the factory ammo as a base/standard and then we can go from there.

Ive shot just factory ammo. Everything in the gun seems original. Ive already ordered the mainspring, extractor spring to replace.

This is my first P08 and Im just trying to get it to run 100%.

My next outting Ill try some winchester white box 115's. I shot 124's because I read thats the best weight for the P08 (ball)

Double check the extractor well for dirt and grit, especially if anything seems to be interfering with it's movement.

Also carefully look at the profile of the extractor to verify it hasn't been chipped or damaged in any way.

You have to dismount the extractor to check the well. There is a small spring in there, so be careful when removing.

Marc

I would suspect either the breechblock is binding, the mainspring is too weak, the firing pin/sear combination is somehow dragging or otherwise interfering with the breech bolt's forward travel, the mag is interfering or some combination of these.

To test the breech bolt for binding, remove the receiver from the frame, remove the toggle from the receiver, and remove the firing pin, spring and firing pin guide. Then slide the toggle into the receiver (with receiver off the pistol), work it throughout its travel to see if there is any binding. There will be a bit of resistance even with a Luger that is functioning properly, but it shouldn't be great. It is helpful to do this with a Luger known to cycle correctly so that you can compare resistance.

The only way I know to test the mainspring is to test fire with a stronger mainspring.

For firing pin/sear proper function, careful inspection and and perhaps careful smoothing with emery cloth of the offending areas if a problem is detected but I'm just guessing based on my knowledge of the mechanism, I've never had a situation where firing pin/sear issues cased the toggle not to close. I would be quite careful in removing material, as it is I suppose possible to make the firing pin release malfunction i.e. the the trigger pull is too light or the pistol fires when not intended, the nightmare of every home gunsmith. Anytime when messing with triggers and sears, consider that perhaps that is job for a genuine gunsmith.

To verify the mag is not the issue, I would test fire the pistol with no magazine, i.e. a single round in the chamber with no magazine in the pistol. The magazine follower button pushing against the hold open device is what causes the pistol to hold-open on last round; with no mag it should return to battery. If the toggle functions correctly with no magazine, but malfunctions with a magazine it, you've isolated the problem somewhat to either the magazine or something the magazine is touching.

My gut says it is the magazine. It is quite surprising how sensitive some Lugers are to which magazine is used. I had to try five magazines, two originals and three MecGars, until we found a magazine that would fix a failure to hold open issue (a different issue than you are dealing with, although similar in that the toggle was not functioning as it should).

Good luck and let us know how it goes.

dacotua:

It appears that you have been provided a full manual for operating and trouble shooting. Others will likewise benefit from this array of info.
Thanks to all.
Jack

I recall reading somewhere that lack of spring tension on the toggle as it moves into the final closed position is one of the innate flaws in the Luger pistol design, and the U.S. Army noted this weakness during their tests and it was one of the reasons the design was rejected. The Luger toggle relies on momentum to seat against the cartridge face.

I look at it like, if we wanted a pistol that didn't have these odd design issues we'd never mess with Lugers to start with. The only good part of these function issues is the feeling of accomplishment when you get a recalcitrant Luger running right. I will be very interested to hear how your testing and fixing goes.

Replace the mainspring, then troubleshoot the problem.

Springs are cheap, and do get tired. I make it a point to replace all springs when I acquire a used pistol.

I got a new mainspring in the mail today, installed it (Thanks to youtube) and went back to the range. This time gun ran 5 magazines without issue.