Breech Block Failure 1916/1920 Erfurt
 

Hello,

I just picked this Luger up over the weekend. I disassembled the pistol and proceeded to clean, check all the parts, lubricate then re-assemble. All of the parts were numbers matching in excellent shape with a great bore and no issues other than standard exterior wear. I just came back from the range where I had fired 3 magazines of 124 grain factory "Blazer Brass" ammunition and noticed this when I went to clean it.

I see no other damage and it still cycles no problem. I assume old metal, probably not safe to shoot as is and I need a new breech block? No other damage was found and I did not notice anything unusual while I was firing the pistol. The block is matching to the gun and marked "57". Any input is appreciated, thank you.

Ouch! It looks like you now have a steeply discounted shooter. This is a good reason why not to shoot a nice matching gun.

Tom Heller or any of a dozen other members ought to be able to hook you up with a new breech block. Best wishes.

Did you pick up your cartridge cases? Surprised with moving that much metal you didn't lose your extractor. Any other interior damage? Firing pin? Metal doesn't just get old. I would head back to the range and hope your brass is still there if you didn't pick it up. There will be one very interesting cartridge case. What does the bolt face look like?

Apparently not even a hot ammo.

Manufacturer CCI Ammunition
Caliber 9mm Luger
Bullet Type Full Metal Jacket (FMJ)
Muzzle Velocity 1090 fps
Muzzle Energy 327 ft lbs
Primer Boxer
Casing Brass Casing

Wonder what went wrong.
Yep, would be interesting to see the cases and the bolt face.
Please post the pics

Bum case perhaps. Pressure tried to blow the extractor out of the top of the breechblock. In a perfect world, everything would be perfect. Not fond of "Blazer" ammo. The cheapest ammo typically gives the cheapest results.

I picked up the brass and no issues. I pulled the block out and no damage to the face or the extractor. I have never had a problem with "Blazer Brass" in any of my other firearms. I did not feel anything like a hot load either.

Thank you, at least the extractor has no damage.

Metal fatigue, been getting "worse" for over 100 years and finally gave up.
No "damage" to the extractor would confirm this was no "overload" situation.


The thin shelves that hold the extractor in place are the most common failure of a breech bolt,
and the only one I have seen- other than perhaps an enlarged hole for the striker nose.

There are plenty of breech blocks around now- some new and recent imports from Germany.

Wouldn't that damage require high pressure gas behind the case head before the toggle unlocked?

Pierced primer?

What does the tip of the firing pin look like? How far does it protrude from the breech face?

If it was dry fired a lot without anything to stop the firing pin, it may have opened up the firing pin hole in the breech face.

I am posting all of the requested photos. I apologize up front for any quality issues and or operator issues. I am trying to respond to people however, it appears the response just shows up in no particular order and not to whom I responded? Thanks again for all of the help.

Photos part 2.

You have a lot of pierced, or at the very least extremely hard hit, primers in the spent brass.

Allen et al, I do have a good supply of exc condition WW1 or 2 original serialized breech blocks @$100 each or new unmarked ones @$90 + $10 US priority S&h for either. TH

I don't see any pierced primers.

Could just be the blurring of the picture. But those primers seem to be dented awfully deep from the firing pin impact.

I checked all of the primers with a magnifying glass for any that may have been pierced and found none. The photo is not real good and compared to the primer strikes on the brass from one of my modern 9mm pistols there is no real difference.

no offense, but do you have a before picture? Perhaps it was already damaged and just blew it out further...

I personally have blown out two breechblocks, but both were the rear and using too hot of ammo.

Ed

We have seen this kind of damaged breech before.
https://i.imgur.com/SBA4Zvv.png

https://i.imgur.com/oxaCPAN.png https://i.imgur.com/cPeAzzX.png

http://forum.lugerforum.com/showthre...ghlight=damage

I blew out one breechblock, but like Ed, it was to the rear.

Thank you everyone for all of the information. Regardless of what caused the damage it looks like I need a new block and I have sent a message to Tom Heller to see if he has one marked "57".

Wh at typically causes this; metal fatigue? Also, what would be the most likely cause of pierced primers; striker spring?

Pin issues
 

Hi Grant, the two most common is, excessive headspace, and/or a deformed firing pin tip. (corroded, sharp point/edge) I'd say that covers about 99% of the pierce primer problems with factory ammo... best, GT

The metallurgy of Erfurt parts also wasn't as good as DWM's. And even DWM had consistency issues with the steel they used.

Personally, I wouldn't shoot an Erfurt at all.

Never shot identical lugers built 100 years apart?
 

If i understand correctly metal fatigue accumulates with multiple bangs over period of time, correct? The shooting/use are the main culprits.

Is there any damaging structural chemical/physical process in an old gun's metal [ or any metal/alloy] even without any shooting or physical use?


LET'S SAY THE SAME METALLURGY, FORGING , TOOLING, MACHINNING- THE IDENTICAL 2 GUNS MADE A 100 YEARS APART. NEVER SHOT. IS THE OLDER ONE MORE LIKELY TO BREAK SIMPLY FROM AGING?

TY

I got this 1937 S42 Mauser in 1982, it already had the breech block failure. All matching except for mag and grips, with a rough bore. It is my "shooter". Only one of my lugers I ever shoot.

In theory the older gun is more susceptible to breakage due to the fact that metal crystalizes over age but in practice the amount of possible crystallization over 100 years would be considered negligible.

I shoot my Lugers as none are family heirlooms, specialty or mint. I have a WWI DWM that the GI had nickel plated with all numbers matching brought back that I purchased from the family and it functions just fine. I am the one that started this post and I plan on replacing the breech block and shooting the Erfurt on occasion is that a bad idea? I have a message and an e-mail into the "lugerdoc@charter.net" to see if he has one that matches the last 2 digits of the serial number. If he does not have one or I do not hear back I will either purchase a new one with no marks or a used non matching I have seen and replace the damaged one. if the majority of members suggest I not shoot it then it is no good to me and I guess I will sell it?

I wonder if repairing by micro welding would work.
Technology has advanced quite a bit.

I have an all matching Erfurt LP.08 as a shooter, but it has been refinished. Even then, when I shoot my shooter Mauser P.08 (matching frame and upper receiver with mismatched Mauser toggle train) it just feels more solid and sturdy in the metallurgy.

I keep two complete toggle trains in my gun safe, one a P08 and the other an LP08. Anytime I shoot one of my Lugers I first exchange the toggle train.

I'm wondering if there would be an issue with hardening Vlim, would you heat the entire area and then quench or ????

Micro or laser welding should not affect the hardness of the surrounding metal as far as I'm aware.

just me, but....
 

I would have it TIG welded maybe partially submerge/bury it in something to reduce the heat and perform as a sink..:eek: Then re-machine, and re-temper/draw back and then refinish...:cheers:...GT

I have a few observations as an amateur that may not be relevant. First of all, I am not familiar with Blazer ammo but generally, in my experience, newly-manufactured ammo has a brass finish primer, like the bass case. These primers are white, like reloads. Is this new ammo or reloaded ammo?

Second, I agree that the primer strikes seem to be unusually deep (see especially the top round in the photo with the breech block from the rear).

I also note from the photo with the breech block face that the striker hole is off center and seems to be “cratered,” raised around the hole. Is the breech block surface flat?

Finally, in looking at the spent brass, most of the brass has the distinctive neck mark from the stepped chamber of the Luger, but several rounds do not seem to have this mark, suggesting that the round did not fully expand into the chamber. Perhaps a sign of firing out of battery?

KFS

It's likely. But it would need to be cleaned up afterwards, and refinished. It comes down to the results of a personal cost/benefit/happiness analysis!

Jim French repaired a Zamak frame for one of my Ermas. It might be worth getting a quote. jmfmicroweld@earthlink.net

Karl,

I used factory ammo purchased at a chain sporting goods store about one month ago.

Poor photos the primer strikes are no deeper than what my Glock, Colt, Walther P-38 and so on spit out.

The breech face and the firing pin opening are the same as my 1916 DWM and are not damaged.

I guess I'm not sure how the pistol would fire "out of battery" but I am willing to listen. I took the pistol apart, cleaned it and inspected every part before I shot it and there was not any damage at that point. I am the only one that shot the pistol and didn't notice any issues when firing it. I only found the damage upon returning to my home when I went to clean the pistol. I am in agreement that it may have just been a breech that had weakened or something else.

Sure, the welding is the easy part.
Having the right size cutter to recut the extractor slot, and then undercut the grooves for the "wings" is the tough part.

I don't think there is any way it could be economical- unless for a really valuable pistol; but then, why would it have been shot.

Just replace the breech block and move on.

No need to look for reasons related to the ammo or other, the darn block was just worn out, old, crystalized, or had a manufacturing defect or steel problem from the beginning and "finally" gave up after 100 years of use. JMHO. :D

After spending 1/2 day researching the pros and cons of micro or laser welding and their affects on gun metal and finish the only economical and simple solution is 'replace the breech block' ... done and dusted and returned to service in an afternoon. :thumbup:

When you do install a different BB, be sure to check the head spacing, as that may have caused your current problem. TH

In particular, the toggle train is, in fact, a long series of parts with axle pins holding the train together.

Wear at any of these axle pin points will contribute to headspace problems, and actually be additive.

I once had a LP08 that kept breaking axle pins between the breech block and the middle toggle. I finally solved the problem by replacing that axle pin with an oversized pin (by .5mm). which lengthened the toggle train and stabilized it.

Check and see how much play (front to back) is in the toggle train. That could have been the initial problem that let gas bypass the cartridge oblation ring and enter the breech area. Remember that the 9mm Luger cartridge body is slightly conical to aid in extraction. It doesn't take much toggle train looseness to contribute to a headspace problem and allow this to happen.

Something was loose enough for the gas to bypass the cartridge body before it came completely out of lock. If it didn't come through a pierced primer hole, it had to travel some route around the cartridge case.

As you replace the breech block, consider that the other two axle pins may be holding worn middle or rear toggles in the train as well.