Trigger job?

javaduke · 03-29-2020, 10:07 AM

Folks, I'm new here, I recently bought a 1913 DMW Luger, the numbers are not matching and it was in a relatively bad shape, so I decided to practice my restoration skills on it and use it as a shooter. I detail stripped it, removed the old paint (yes, somebody sprayed black paint all over it), cleaned it up and rebelled, now it looks pretty good now but the trigger pull is awful. It is very gritty and long. So I'm wondering what is the best way to improve it? Doesn't have to be light, but I'd like it to be smoother. What is the proper way to address this?

Major Tom · 03-29-2020, 10:24 AM

I know the trigger system in a luger is complicated. There should be some insight here in this website. Take a look around.

Lugerdoc · 03-29-2020, 01:24 PM

J Duke, For a shorter trigger pull, you will have to reduce the overlap of the striker and sear. Also flattening out the flat sear spring will lighten the force required. Unfortunately, taking either of these steps too far may lead to the pistol wanting to go full auto. TH

rhuff · 03-29-2020, 04:10 PM

Your Luger may well have the wrong trigger return spring installed(too strong). Lugers do not have great, target trigger pulls, as many were war products. They can be improved, but go carefully for they can go full auto.

DonVoigt · 03-30-2020, 09:04 AM

I'd clean it well and lube; then leave it alone.

There is not much upside to improving the trigger, and lots of "down" side. JMHO.

Ray · 03-30-2020, 03:40 PM

here is an article that I saw in a shooting magazine years ago
Ray in Oregon

*** Mod Addition *** High Resolution PDF is in post 18 Below ***

mrerick · 03-30-2020, 10:30 PM

*** See Below for PDF copy in High Resolution *** And accept the caveat that the author didn't have the correct reverse angle information Don discusses below.

- - - - - -

In spite of the good information in the article, Luger trigger adjustment is as much an art as anything else, and that art is likely based on some experience.

As Don says, we hear much more often about problems caused than improvement achieved.

Most everything in the complete linkage affects other parts, some of which are covered during operation.

DonVoigt · 03-31-2020, 01:04 AM

Great write up, BUT- the reverse angles that give the luger a heavy trigger pull are necessary for the sear and striker to firmly and safely engage- messing with the angles and amount of engagement is asking for :
a- failure to ****Kyock
b- doubling
c- full auto fire
d- unexpected discharge without touching the trigger!

K.Wilhelm · 03-31-2020, 10:09 AM

Amen to what's been said. I've had two Lugers fire upon toggle closure (finger not on trigger)- not a fun experience! I didn't do anything to these triggers, but I suspect the previous owner(s) did.

Sergio Natali · 03-31-2020, 10:24 AM

Quote:

Originally Posted by DonVoigt

I'd clean it well and lube; then leave it alone.

There is not much upside to improving the trigger, and lots of "down" side. JMHO.

Quote:

Originally Posted by DonVoigt

Great write up, BUT- the reverse angles that give the luger a heavy trigger pull are necessary for the sear and striker to firmly and safely engage- messing with the angles and amount of engagement is asking for :
a- failure to ****Kyock
b- doubling
c- full auto fire
d- unexpected discharge without touching the trigger!

I agree completely with Don, leave it as it is.

Olle · 03-31-2020, 10:28 AM

Quote:

Originally Posted by DonVoigt

Great write up, BUT- the reverse angles that give the luger a heavy trigger pull are necessary for the sear and striker to firmly and safely engage- messing with the angles and amount of engagement is asking for :
a- failure to ****Kyock
b- doubling
c- full auto fire
d- unexpected discharge without touching the trigger!

This was my immediate observation as well. Interestingly, the author states that he has observed this "flaw" in every Luger he has examined, and he still doesn't understand that it's made like that on purpose. BTW: The same "flaw" can be found in mil spec AR-15 triggers, and people are still trying to "correct it" with the same results as you mention.

mrerick · 03-31-2020, 11:03 AM

What leads to the need for the negative sear engagement?

How much is it (angle?)

Is this because of the potential for "bounce" of the slide when it comes back into battery after firing a shot? Or is it needed to draw the sear and firing pin together when it comes into battery?

Why is the single stage AR-15 designed with this engagement?

I think a description of the thinking behind the negative sear engagement would make a good FAQ entry... Marc

Ray, if you can get higher resolution scans of the article to me, I'll make it into a PDF file.

Marc

Kiwi · 03-31-2020, 12:26 PM

My first 1911 had a trigger pull that felt like dragging a knife blade over rough concrete. The 1911 sear is case hardened maybe 1/1000 inch thick is hard. But examination under magnification showed manufacturing burrs, removing them (fine Arkansas stone) made a nice trigger.

I would limit any trigger work to similar smoothing. Changing angles is extremely risky, and best done with easily replaceable parts (Oops, start again), not Luger fitted and numbered parts.

Ron Wood · 03-31-2020, 12:42 PM

Marc,
I have that trigger tune article in .jpg format that is pretty legible and I can save the pages in .png format if that would be better. Either format can be expanded.
Ron

HerrKaiser · 03-31-2020, 01:27 PM

Of my four, only my refinished LP-08 has a clearly noticeable trigger "wall" before the break. The others are a bit mushy with takeup and are difficult to get a grasp on where the sear will "break". I do not worry about it too much since they do not malfunction, and it isn't like I am using them for anything other than as range toys or safe queens.

DonVoigt · 03-31-2020, 03:56 PM

Quote:

Originally Posted by mrerick

What leads to the need for the negative sear engagement? Think about it, if there is no negative angle there is nothing to prevent the sear and striker from slipping off each other- due to creep under spring tension or movement/vibration of the parts or entire pistol.

How much is it (angle?) I believe it is too small /short to measure accurately- it may be in the drawings.

Is this because of the potential for "bounce" of the slide when it comes back into battery after firing a shot? Or is it needed to draw the sear and firing pin together when it comes into battery?
The sear/striker are engaged before the slide finally closes, but yes -the angle is needed to assure that the two surfaces stay engaged.

Why is the single stage AR-15 designed with this engagement?
The AR sear/hammer are an entirely different arrangement; but in general all sear engagement uses a "correct" angle or geometry to assure engagement until moved by the trigger/trigger bar.

I think a description of the thinking behind the negative sear engagement would make a good FAQ entry... Marc

Ray, if you can get higher resolution scans of the article to me, I'll make it into a PDF file.

Marc

See comments above.

Kiwi · 04-01-2020, 10:19 AM

Out of curiosity I examined the firing pins of my 2 last night.
Under an 8x Loupe both had crud on the surface engaged by the sear.
Crud being microscopic bits of either metal or powder stuck to the surface with oil.
Actually looked more like fine metal filings (not me) than powder

A toothbrush and cleaning patch.
Unfortunately I am in a lockdown State and cannot field test the result at this time

mrerick · 04-01-2020, 10:35 AM

Ron was good enough to provide high resolution scans of the article. I've attached it here.

Marc

4 Scale · 04-01-2020, 04:34 PM

What I like about that article is that several times the author admonishes the reader to fully understand the firing mechanism before attempting any improvements. If that advice is followed and the pistol's operation observed carefully it should be possible to determine what might be causing the poor trigger performance.

I would suggest complete disassembly (including removal of the sear bar and transfer lever), inspect (preferably with magnification), clean lubricate then reassemble and test before attempting any physical adjustments. The only time I fiddle with trigger components is to correct malfunction. To me, getting good accuracy without resorting to physical modification is part of the fun and challenge of firing older firearms.

I when I find myself missing nice triggers I shoot modern pistols.

DonVoigt · 04-01-2020, 06:15 PM

Luger triggers are no worse than an out of the box Glock, or one of the other DAO pistols, IMO.
Many are somewhat better!

03-29-2020, 10:07 AM	#1
javaduke New User Join Date: Mar 2015 Posts: 1 Thanks: 0 Thanked 0 Times in 0 Posts	Trigger job? Folks, I'm new here, I recently bought a 1913 DMW Luger, the numbers are not matching and it was in a relatively bad shape, so I decided to practice my restoration skills on it and use it as a shooter. I detail stripped it, removed the old paint (yes, somebody sprayed black paint all over it), cleaned it up and rebelled, now it looks pretty good now but the trigger pull is awful. It is very gritty and long. So I'm wondering what is the best way to improve it? Doesn't have to be light, but I'd like it to be smoother. What is the proper way to address this?

03-29-2020, 10:24 AM	#2
Major Tom User Join Date: Jan 2017 Location: S.E. Iowa Posts: 481 Thanks: 531 Thanked 226 Times in 123 Posts	I know the trigger system in a luger is complicated. There should be some insight here in this website. Take a look around. __________________ I Build Custom Pistol Boxes

03-29-2020, 01:24 PM	#3
Lugerdoc Patron LugerForum Patron Join Date: Jun 2002 Location: POB 398 St.Charles,MO. 63302 Posts: 5,089 Thanks: 6 Thanked 736 Times in 483 Posts	J Duke, For a shorter trigger pull, you will have to reduce the overlap of the striker and sear. Also flattening out the flat sear spring will lighten the force required. Unfortunately, taking either of these steps too far may lead to the pistol wanting to go full auto. TH __________________ Tom Heller POB 398 ST.Charles, MO. 63302 Tel 636-447-3006 lugerdoc@charter.net

03-29-2020, 04:10 PM	#4
rhuff Patron LugerForum Patron Join Date: Mar 2011 Location: Az. Posts: 2,270 Thanks: 2,686 Thanked 958 Times in 704 Posts	Your Luger may well have the wrong trigger return spring installed(too strong). Lugers do not have great, target trigger pulls, as many were war products. They can be improved, but go carefully for they can go full auto. __________________ Need DWM breechblock #21

03-30-2020, 09:04 AM	#5
DonVoigt User Join Date: Apr 2015 Location: near Charlotte NC Posts: 4,677 Thanks: 1,439 Thanked 4,347 Times in 2,038 Posts	I'd clean it well and lube; then leave it alone. There is not much upside to improving the trigger, and lots of "down" side. JMHO. __________________ 03man(Don Voigt); Luger student and collector. Looking for DWM side plate: 69 ; Dreyse 1907 pistol K.S. Gendarmerie

03-30-2020, 03:40 PM	#6
Ray Patron LugerForum Patron Join Date: Jun 2002 Location: Oregon Posts: 126 Thanks: 2 Thanked 37 Times in 16 Posts	improving luger trigger here is an article that I saw in a shooting magazine years ago Ray in Oregon * Mod Addition * High Resolution PDF is in post 18 Below *** Attached Thumbnails Last edited by mrerick; 04-01-2020 at 10:39 AM.

03-30-2020, 10:30 PM	#7
mrerick Super Moderator - Patron LugerForum Life Patron Join Date: Dec 2009 Location: Eastern North Carolina, USA Posts: 3,900 Thanks: 1,370 Thanked 3,094 Times in 1,503 Posts	* See Below for PDF copy in High Resolution * And accept the caveat that the author didn't have the correct reverse angle information Don discusses below. - - - - - - In spite of the good information in the article, Luger trigger adjustment is as much an art as anything else, and that art is likely based on some experience. As Don says, we hear much more often about problems caused than improvement achieved. Most everything in the complete linkage affects other parts, some of which are covered during operation. __________________ Igitur si vis pacem, para bellum - - Therefore if you want peace, prepare for war. Last edited by mrerick; 04-01-2020 at 10:37 AM.

03-31-2020, 01:04 AM	#8
DonVoigt User Join Date: Apr 2015 Location: near Charlotte NC Posts: 4,677 Thanks: 1,439 Thanked 4,347 Times in 2,038 Posts	Great write up, BUT- the reverse angles that give the luger a heavy trigger pull are necessary for the sear and striker to firmly and safely engage- messing with the angles and amount of engagement is asking for : a- failure to ****Kyock b- doubling c- full auto fire d- unexpected discharge without touching the trigger! __________________ 03man(Don Voigt); Luger student and collector. Looking for DWM side plate: 69 ; Dreyse 1907 pistol K.S. Gendarmerie

03-31-2020, 10:09 AM	#9
K.Wilhelm User Join Date: Jun 2013 Location: South Central Colorado Posts: 215 Thanks: 45 Thanked 109 Times in 66 Posts	Amen to what's been said. I've had two Lugers fire upon toggle closure (finger not on trigger)- not a fun experience! I didn't do anything to these triggers, but I suspect the previous owner(s) did. __________________ NRA Endowment Life member Proud veteran of the Naval Security Group

03-31-2020, 11:03 AM	#12
mrerick Super Moderator - Patron LugerForum Life Patron Join Date: Dec 2009 Location: Eastern North Carolina, USA Posts: 3,900 Thanks: 1,370 Thanked 3,094 Times in 1,503 Posts	What leads to the need for the negative sear engagement? How much is it (angle?) Is this because of the potential for "bounce" of the slide when it comes back into battery after firing a shot? Or is it needed to draw the sear and firing pin together when it comes into battery? Why is the single stage AR-15 designed with this engagement? I think a description of the thinking behind the negative sear engagement would make a good FAQ entry... Marc Ray, if you can get higher resolution scans of the article to me, I'll make it into a PDF file. Marc __________________ Igitur si vis pacem, para bellum - - Therefore if you want peace, prepare for war.

03-31-2020, 12:26 PM	#13
Kiwi User Join Date: Mar 2019 Location: Wrong side of the Delaware river Posts: 291 Thanks: 199 Thanked 413 Times in 162 Posts	My first 1911 had a trigger pull that felt like dragging a knife blade over rough concrete. The 1911 sear is case hardened maybe 1/1000 inch thick is hard. But examination under magnification showed manufacturing burrs, removing them (fine Arkansas stone) made a nice trigger. I would limit any trigger work to similar smoothing. Changing angles is extremely risky, and best done with easily replaceable parts (Oops, start again), not Luger fitted and numbered parts.

03-31-2020, 12:42 PM	#14
Ron Wood Moderator 2010 LugerForum Patron Join Date: Jun 2002 Location: Santa Teresa New Mexico just outside of the West Texas town of El Paso Posts: 6,986 Thanks: 1,065 Thanked 5,088 Times in 1,674 Posts	Marc, I have that trigger tune article in .jpg format that is pretty legible and I can save the pages in .png format if that would be better. Either format can be expanded. Ron __________________ If it's made after 1918...it's a reproduction

03-31-2020, 01:27 PM	#15
HerrKaiser User Join Date: Feb 2018 Location: South Carolina Posts: 800 Thanks: 750 Thanked 793 Times in 376 Posts	Of my four, only my refinished LP-08 has a clearly noticeable trigger "wall" before the break. The others are a bit mushy with takeup and are difficult to get a grasp on where the sear will "break". I do not worry about it too much since they do not malfunction, and it isn't like I am using them for anything other than as range toys or safe queens. __________________ -QM Looking for Mauser S/42 toggle train #22

04-01-2020, 10:19 AM	#17
Kiwi User Join Date: Mar 2019 Location: Wrong side of the Delaware river Posts: 291 Thanks: 199 Thanked 413 Times in 162 Posts	Out of curiosity I examined the firing pins of my 2 last night. Under an 8x Loupe both had crud on the surface engaged by the sear. Crud being microscopic bits of either metal or powder stuck to the surface with oil. Actually looked more like fine metal filings (not me) than powder A toothbrush and cleaning patch. Unfortunately I am in a lockdown State and cannot field test the result at this time

04-01-2020, 04:34 PM	#19
4 Scale User Join Date: Nov 2014 Posts: 544 Thanks: 194 Thanked 489 Times in 251 Posts	What I like about that article is that several times the author admonishes the reader to fully understand the firing mechanism before attempting any improvements. If that advice is followed and the pistol's operation observed carefully it should be possible to determine what might be causing the poor trigger performance. I would suggest complete disassembly (including removal of the sear bar and transfer lever), inspect (preferably with magnification), clean lubricate then reassemble and test before attempting any physical adjustments. The only time I fiddle with trigger components is to correct malfunction. To me, getting good accuracy without resorting to physical modification is part of the fun and challenge of firing older firearms. I when I find myself missing nice triggers I shoot modern pistols.

04-01-2020, 06:15 PM	#20
DonVoigt User Join Date: Apr 2015 Location: near Charlotte NC Posts: 4,677 Thanks: 1,439 Thanked 4,347 Times in 2,038 Posts	Luger triggers are no worse than an out of the box Glock, or one of the other DAO pistols, IMO. Many are somewhat better! __________________ 03man(Don Voigt); Luger student and collector. Looking for DWM side plate: 69 ; Dreyse 1907 pistol K.S. Gendarmerie