Replacement Holdopen fits well, but toggle not staying retracted with mag

[RShaw]

Hi All!
Some of you may remember my broken holdopen on my shooter 1918 DWM... it has shot fine since then, although it is picky regarding ammunition.

Today I finally received a new holdopen.

I installed it and it fits well; the rear "L" prong rises up when inserting a mag, and drops when the mag is dropped out, but the toggle is not held back as it should be when the mag is in.

I notice that the spring has more of a bend in it than does the original spring. The barrel assembly also does not slide back and forth quite as well since the spring protrudes only slightly into the plane of the rail just above it.

I'm thinking of switching the springs to see if that does anything... if that doesn't work, I'll have to bring it to my LGS. The toggle did stay back once out of many tries. Other mags are also not working. I think it's very close, but it's certainly not doing it's job yet.

Any other ideas out there? What adjustments are "normal" for a replacement HO?
Thanks a lot in advance,

Cheers,
RShaw

[John Sabato]

Remove the right grip and perform your magazine tests without the grip installed. Sometimes the grip hinders the magazine button from moving properly to operate the holdopen. Let us know how that goes... If it works well without the grip installed, then you need to determine where the grip is rubbing the mag button and relieve the contact till it works the way it was designed.

[DonVoigt]

Could be the retaining ledge on the bottom of the breech block is worn, or chipped or has some other problem.

[RShaw]

Well, I tried the mag test without the grips, but no change at all.

I should say that the old holdopen operated flawlessly until the little "L-prong" broke off at the rear. So the ledge should be fine; I don't see or feel a chip there. Unless it chipped when the old HO broke.... I am assuming that that little ledge is the bottom of the leading edge of the breech below where the firing pin exits when firing? One cannot see the edge of the holdopen at all when the toggle is locked back, so I'm not sure where exactly that ledge is located.

Now I see how the mag button pushes up the HO. That seems to be fine. The HO does rise quite a bit when inserting the mag.

Thanks....

[RShaw]

Well, I compared the bottoms of the breech blocks of my 2 P08's, in the photo below the top one is working very well with it's matching HO.

The one in the bottom of the photo is the one which is not catching.
WHile I can see that there is an indentation in that one, it doesn't look like a fresh chip- rather it looks like it's been that way for a longer time. More wear than a chip from years back?

Still the original HO worked great!

Seems as if your point, Don is spot on. I'm hoping I can perhaps change springs to get that new "L-prong" to ride up in there more agressively... and also the new spring restricts the back and forth movement of the barrel assembly, as I mentioned before.

I also tried putting the upper on the bottom in the photo below onto my P08 with the matching and well functioning HO.
The fit was not good at all, so I didn't try to force it. Idea was to see if that good HO would catch the worn breech block. But... no go.

Yes I'm learning a lot, but this gets expensive!!

Can the new spring be bent out to be more straight? Or is trying this a basically bad idea?

Ah well.... there are far worse things...

I appreciate all your feedback, Thank you.

[DonVoigt]

Well,
you could just interchange the toggles and see how the other bolt works.

If it were mine, I'd use a needle file and square up the shoulder of the "bad" bolt, and maybe move it back just a tad; looks a little deformed to me.

I would not bend the spring until and in a last resort, they will snap at the "right angle bend". I might try thinning it a little on some very fine paper if it is too strong.

but I think your problem is the bolt.

[4 Scale]

You mentioned that the original hold open worked flawlessly before it broke. This one seems to mostly not work. It seems to me this fact set isolates the problem to the new hold open part.

You also said the hold open spring on the new part is interfering with the operation of the barrel/receiver assembly. That is not supposed to happen. You might consider posting a photo of this new hold open, in the meantime I think your idea of trying a new hold open spring is a good one. I'd also mention I once had a hold open that was not rising quite far enough to reliably catch the breech bolt on last round, polishing the HO fixed the issue.

Also I would try a hold open from your other Luger and see if that works, as well as trying the toggle assembly from the other pistol.

[DonVoigt]

Is the "new" hold open a reproduction or original? Where did you buy it?

[mrerick]

Is it shadow in the photo, or is the bolt that fails to catch cut square or at an angle?

[Lugerdoc]

The hold open that I sent was a NOS Swiss for the M29. Sometimes the attached spring is a bit too long to fit completely in the slot of a standard PO8 and should be shortened at the front to avoid excess friction with the barrelled receiver. TH