toggles hitting hard on frame
 

I have been reading about how hard a toggle should hit the frame so I tried the tape method. I have 2 lugers; the first set of 3 pictures is a S42 luger. I was shooting Winchester white box 9mm 115 gr. The luger functions great, it cycles, and locks open on empty. It appears to hit harder on the left side of the frame.
The second set of 3 pictures is a commercial DWM 1920’s .30 cal.luger I was shooting Fiocchi 93 gr. The luger functions great, it cycles, and locks open on empty. It appears to hit harder on the left side of the frame. I tore the tape on the right side getting it off.
From the way the toggles are hitting, it appears I need new springs? Wolf looks like the best pick, a 38 lb. for the 9mm and a 36lb. for the .30 cal.
I would appreciate any input! From what I have been reading the .30 cal is a hard spring to get to function correctly.

commercial DWM .30 cal.
 

here is the second set of pictures

Needs a stronger main spring IMO. Wolff Springs sells them. How high is the ejection of brass? That can be another sign. If more than 8'-10' might be too weak on the spring. The 9mm looks like it is hitting harder or has been hit more times.

Thor
I have a dumb question. :o
Do you recommend putting some kind of lubricent or grease on the front of the ears to help the toggle flip up? I have never done this as I never realized the toggle can actually bang the frame ears hard enough to deform them. :banghead:
Does this happen on all lugers or just ones with weak springs or from shooting ammo that is too hot?
I am a big fan of keeping everything lubed.(that sounded weird!):roflmao:
Thanks
Bob

Thor thanks for the quick response. I can’t recall how far the brass went. I think I will get the service pack from Wolf, for the Lugers. Thanks

Guess I have been misinformed. I thought that the "tape test" was conducted by applying the tape to the back of the frame where the rear toggle link impacts to stop the motion of the toggle. A heavy strike there indicates a weak main spring. A heavy strike on the ramp/camming surface of the frame might indicate that the mainspring is quite strong and the toggle knobs, which are held down partially by the strength of the spring, need more force to "break" them upward to unlock the action. Most likely I am wrong...wouldn't be the first time.:)

+ 1

I must be uninformed too, as I can clearly remember the thread w/pics showing the tape and strike marks on the back of the frame... :confused:

I guess it's true about a mind being a terrible thing to waste... :(

Make 100% sense to me. That rear extruding of the 3rd toggle link must be there to perform "bolt stop" function. Weaker main spring should have more recoil energy left, absorbed by the rear end of the 3rd link impacting with the frame, and leaves deeper mark on the rear of the frame.

Agreed. The test depicted may very well show a too strong recoil spring. It would be instructivce to see that the back of the frame looks like. Perhaps no marks at all?

Makes sense to me. Interesting.......things that make you go hmmmmm! Sometimes too strong of a main spring will sometimes, not always, show up in failures to eject, or weak ejections. If the ejection is too strong, and I have seen brass launching a good 15' straight up, you are hammering the gun too hard and take a chance on breaking the ejector. This is assuming a standard load is used, if you start using different pressure loadings you add more variables to the equation. SHEESH.......this is making my head hurt!

Seems the knuckle is not breaking soon enough. Spring too strong? Think how the toggle lock works on early models though.Back, then up. John

I changed the springs in one of my shooters after it broke its third lightbulb above the shooting station at the local indoor range. (with some urging from the range owner).

Forceful, straight up ejection.

I concur that the ear pounding seen in the photos is the result of weak springs, likely combined with hotter ammo than the gun was designed for...

You can break ejectors, I know!

+1 on the straight up ejection. Most of my spent cases never land, but end up on top of the false ceiling at the shooting stand.

Ejectors and extractors break, it's a fact of life. Something to consider when shooting your luger. Parts will wear out and break. Simple as that. Did that in the old days, will do that today. ;)

Help I am now confused?
 

I am now confused about the tape thing. The tape test for a weak spring is to put the tape on the rear receiver where the rear toggle link tail hits the back face of the receiver? I read the e-book on lugers and it said this: The toggle knobs reach and follow the ascending slopes at the rear of the frame, the toggle joint is accelerated rapidly up past dead center. The rear slopes of the receiver and other areas which can give good clues to knowing whether the gun was used intensively. Repetitive strikes of the toggle knobs against the slopes progressively crush polish them. In some rare cases of heavy use, the metal can be deformed. On the other end of this wear spectrum a luger with little use, the receiver slopes are still retaining almost all their blue finish. On the subject of the rear toggle link’s tail, the e-book said that with time traces of wear appear on the back face of the receiver. These traces are good indicators whether or not the pistol was fired a lot. So here is the question, if repetitive strikes of the toggle knobs on the slopes over time causes wear, then this is only a sign of heavy use? Then using the tape method on the back of the receiver is the best way to check for weak spring? If it passes the tape test then leave the spring alone?

The tape test is indeed performed at the rear of the frame, not in the toggle area (although it is a nice test to check the 'balance' of both toggle knobs. If one is out of sync with the other, it will cause the gun to shoot slighly to the left or right, depending on the knob.

Matching the knobs to the frame is critical for accuracy, and Mauser got their new Parabellum parts tolerances to such a high degree that they only had to match the rear toggle with the frame/receiver. That is the reason why on the MP only the rear toggle part has part of the serial number engraved on it.

But back to the test. If the main spring is to weak to slow the toggle down, or the ammunition is too spicy (fast burning powders or too much powder), the toggle will flex past it's stopping point, leaving a clearer marking on the rear of the frame. This is checked with the 'tape test'. It shows how hard the rear end of the toggle hits the frame.

The initial powders developed for the Parabellum pistol were basically rifle powders and had a slower burning rate than the modern pistol powders. This produces a different pressure curve, which produces different recoil characteristics.

The shape and location of the frame ear curves have been altered a number of times. The Swiss especially experimented heavily with the curve shape, and the 06/29 shape was tuned to that particular pistol, barrel length, spring and ammunition. Mauser, who based their 1970s design on the 06/29 found that the Swiss curve was ideal for the 06/29 but gave difficulties with other barrel lenghts and calibres. They eventually moved the Swiss curve a few millimeters to the rear in order to avoid further recoil issues.

I am surprised on this one....

When the knob touches the ramp, is the bullet still in barrel?

Alvin, repeat shots will 'walk' to the left or right with rapid firing.

The C96 had a similar problem initially, but there the 'wobble' was in a vertical direction.

One more reason to favor the W+F 06/29 with its strengthened, drop-in extractor! :D