Full Auto Luger (PO8)


August 23, 2007, 01:36 PM
Have owned this 9mm Luger for about 20 years. Postwar Mauser manufacture. Been a good shooter but in recent trips to the range it started doubling and tripling. Now a machine pistol is fun to fire but a single action that surprises you is down right dangerous. The piece is kept extremely clean including the firing pin and bolt, no excessive wear that I can tell. Have any of you Luger owners had this experience and if so can you direct me to a possible fix or fixes. Thanks.

If you enjoyed reading about "Full Auto Luger (PO8)" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
August 23, 2007, 01:40 PM
I don't think I would admit to this in public. Get to a gunsmith immediately before you get the ATFers breathing down your neck...

August 23, 2007, 01:42 PM
Wow had 1911 with some sear/disconnector/ hammer issues go full on me once. Scared the living daylights out of me, most embarassingly it was at a range. It got taken apart and new parts right there. Never seen that with a Luger eesh!

robert garner
August 23, 2007, 01:57 PM
Got some serious looks when my sks started doubling and even trippling at the range, seems that modern lubes will do that with some of these. Are you using
tri-flow or something simular? clean it and use something less slippery!

August 23, 2007, 02:11 PM
Take the gun apart. Under the side plate you will find a right angled crank lever called the trigger lever. Examine the upper end closely. Look at the rear edge of the upper end for wear. The disconnector is a small spring loaded plunger in the front end of the sear on the side of the receiver rail. Make shure it moves freely. Look inside the rail and check the sear for wear. Remove the striker and check the sear engagement on its left side for wear. Make sure everything is clean and properly lubed. Let us know what you find.

If all else fails, go to http://www.lugerforum.com/ this is where the Luger gurus reside.

August 23, 2007, 02:23 PM
I've seen a "home-tuned" CZ or HP go fully-automatic. That was definitely NO fun:eek:

August 23, 2007, 02:47 PM
I would say it's not really "full-auto" but rather, broken.
Broken usually means it will double, triple, or in one case I had one that would fire until the mag was empty, or until it jammed. Just letting up on the trigger didn't stop it. (Thankfully it was a .22 so I could hold it down.)
Uncontrolled fire in a handgun usually means a whole bunch of rounds in the ceiling because the cyclic rate is so high it can't be held down.

August 23, 2007, 02:56 PM
Yes, you're right. Not really "full auto". It fired till the magazine was empty. Rather scarry experience I think. I hope it never happens to me. I won't change anything on my guns without competent instruction.

Ron James
August 23, 2007, 07:32 PM
On the same subject, my wifes grandfather gave her a like new Ortgies .25 . cleaned it, took it to the range, pulled the trigger and ZOOM, 6 rounds downrange , one pull of the trigger. It takes a couple of seconds to realize what just happened. I do believe the last round was at a 45 degree angle.:uhoh:

August 23, 2007, 08:39 PM
i got a new MPA930 that still scares me...the first couple times i emptied the mags into the range ceiling....i put a muzzel brake on it...now at lest i can keep it on the back stop....i did send it back to the factory, they found no problems.....gpr

Hk91 Fan
August 23, 2007, 08:56 PM
This is not all that unusual with Lugers. Check the Luger forum.

August 23, 2007, 09:35 PM
Somthing with an M1911 type frame should be made a machine pistol like the Stechkin APS or the M93R.

August 23, 2007, 10:27 PM
Somthing with an M1911 type frame should be made a machine pistol like the Stechkin APS or the M93R.

It's been tried. I think Star, Mendoza or something similar did it. Even with some kind of a rate reducer and a shoulder stock they are nearly unmanagable.

Bart Noir
August 24, 2007, 03:03 PM
My brother once was responsible for a whole bunch of Uncle Sam's 1911 pistols and parts for them. So he just happened to modify parts and drop them into a pistol to see what a full-auto 1911 was like.

It was negative fun.

Bart Noir

August 24, 2007, 05:05 PM
Think I'll take the Mauser Luger that thinks it's likeing the idea of becomming a machine pistol to my gunsmith when I get back to FL in Nov. The trigger lever engages with the disconnector well and the disconnector moves freely in the fwd end of the sear. Must be some slight out of tolerance wear on the inside of the sear or on the side of the striker that engages the sear that is not noticable to the untrained eye. The Luger had to have been designed by some very brilliant guy who resided in a insane asylum and a close cousin to Rube Goldberg. My thanks to all who have responded.

January 19, 2010, 01:59 PM
Reviving an old thread. What was the fix to the full auto problem on the Luger? Anyone have any ideas? Feel free to PM with ideas/solutions. Thanks.

January 19, 2010, 06:53 PM

heres a full auto broomhandle mauser

January 19, 2010, 07:02 PM
Georg Luger (No "e" on Georg.) designed the Luger. It was a redesign of the Borchardt and greatly simplified, streamlined, lightened, and generally improved on the Borchardt. The Borchardt in it's turn was inspired by the Maxim machine gun. Some say the Maxim was inspired by the steam engine.

Maxim was an American inventor noted for the suppressor among many other inventions.

Borcahrdt was a German-American who worked for Winchester and Sharps.

So you see, at bottom, the Luger has American roots.

January 19, 2010, 11:23 PM
how do you prevent/fix the luger from going full auto on you?

Jim K
January 20, 2010, 06:29 PM
There isn't a way to absolutely "prevent" any semi auto from doubling or even going full, but it is not designed to work that way, so the cause is almost always either wear or tampering (sometimes with the intent of making a FA weapon). The "fix" is to replace any damaged or worn parts.

It is nearly impossible for simple wear to turn a semi-auto into a reliable and safe full auto, although some guns are more prone to problems than others. The aforementioned Ortgies is one. It uses a straight drive striker which has two arms, but only one is actually held by the sear. If it breaks in a certain way, it can catch the sear just enough to delay firing pin drop until the slide closes and then fire, going FA. Just firing pin follow down will not reliably fire the gun.

I have known of a number of semi-autos that went full through no fault of the owner, but I have never known BATFE to take any action (except to tell the owner to have it fixed) except when there was clear evidence of tampering with the intent of making a machinegun. There was a recent case in which such a charge was made; the owner, as usual, claimed that the cause of the auto fire was simple wear. Some gun folks automatically supported him, but (AFAIK) neither he nor BATFE has provided any definitive technical description of the gun or its parts or how it went full auto.

(FWIW, there have been several designs for converting the Luger to a machine pistol; none went beyond the experimental stage and no Lugers were ever made originally in a full auto configuration.)


January 20, 2010, 08:29 PM
Long story, as short as I can make it...
A friend of mine was reading, I think, Bill Jordan, who said that he practiced drawing his revolver with his weak hand (in case of arm injury) and holding and shooting it upside down. Trigger pull was done with the pinky.
So we're shooting in the woods and Good Friend draws his PPK with his left hand, upside down, and pulls the trigger, per the book.
Said pistol went full-auto until somehow his finger retracted the trigger guard and the slide flew off the front of the gun.
I don't recall if he tried it again, but he shot hundreds of rounds through that pistol, and it worked flawlessly as designed when fired right-side-up.

January 20, 2010, 08:52 PM
First and obvious thing would be to tear it down, make sure it's clean and properly lubed, look for any obviously worn or broken parts, etc.

Past that, while I'm pretty familiar with how a Luger works properly, I don't claim to be any expert on what makes them go full auto. I would consider it a dangerous condition. If the striker drops before the action is fully locked the pistol can fire. Firing with out the action fully locked up doesn't bear thinking about.

I would take a very close look at the upper part of the trigger lever, the dis-connector, the sear, and the notch.

The trigger lever is the movable piece in the side plate after you take it off. The upper end should have a little ramp that lets the dis-connector slide forward when the trigger is released.

The dis-connector is the little spring loaded plunger in the front end of the sear bar. It should move freely.

The sear is on the other end of the sear bar and is seen inside the frame when torn down.

The notch is not really a notch in the Luger, but a flat surface on the front of an ear on the striker that protrudes through the left side of the block.

When the breech block returns to battery, the sear stops the striker from going all the way forward with the breech block, thus cocking the striker.

With the pistol assembled, and double checked to be sure it's empty, pull the toggle back and allow it to go forward very slowly. On the majority of Lugers the breech block will stop when the sear engages and not go all the way forward. Jiggle the action a bit and see if the striler will slip off the sear. If not, then at this point you can pull the trigger and check for a proper release. The trigger should be a military style two stage trigger with some slack take up and then stiffen before breaking. If the Luger is a poorly fitted mismatch the trigger may be creepy, but it should not do anything really funny.

Go to http://www.lugerforum.com/ and ask there. (You will have to sign up.) That's where all the Luger gurus hang out. I'm sort of one of them, but going full auto is not my area of expertise. Luger Doc could probably give some advice.

If you enjoyed reading about "Full Auto Luger (PO8)" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!