Reinforced Frame, Part 2

[Dwight Gruber]

Even with the recoil spring well situation firmly under my belt, something has continued to bother me about the whole â??reinforced frameâ?� thing. Writers have referred to it as though it is significant without really making it clear, and I have never really managed to wrap my mind around it.

In a chance reading of an old â??Lugers at Randomâ?� column about LP-08 (Gun Report August 1994) Kenyon discussed some Luger production details, including the frame reinforcement, and I suddenly had a much better idea of what might be involved. It is not the frame spur, but something else entirely. In case you don't have the issue at hand I'll quote the pertinent text:

"Post 1914 Machining Changes
"...the introduction of the LP-08...resulted in significant changes in standard machining procedures at both DWM and Erfurt. These changes were reflected in all Lugers produced for the German military thereafter.

"At DWM: ...a reinforced area (less metal machined away) at the upper inner rear area of the frame where the lanyard loop is attached. This modification probably was to buttress the frame against the greater impact of the recoiling toggle assembly [longer barrel = higher velocity, improved ammunition].

"At Erfurt Arsenal: ...Erfurt Lugers from their inception had the frame reinforcement in place."

--Gun Report August 1994, "Lugers at Random" column, Charles Kenyon

I was still having trouble visualizing what he meant, so I pulled out some Lugers and took them down; and once I knew what to look for and where it was very obvious.

My most recent confusion about the subject came from reading Walter, and it was the direct cause of the frame spur survey. Part of the problem in comprehension is that Walter is not very clear, and he is actually referring to two different things.

In The Luger Book on p.117 he mentions frame reinforcement, and refers an accompanying dimensional drawing This drawing does not actually point the reinforced area out, or illustrate a difference. If you don't already know what the frame reinforcement is, you will not be able to figure it out, as I was not able.

In Luger on p. 209, Mechanical changes 1900-45, he uses the term â??reinforcementâ?� in the context of the recoil spring well spur. It takes a close reading to realize that he is not talking about the back-frame reinforcement. Even more confusing is the fact that the changeover of both of these features occurs in the same time frame. In addition, the back-frame reinforcement itself is never mentioned in this section of Luger. This completely confuses the issue; by using both books as a reference for the topic one is thrown completely off track.

I'm not set up to make direct comparison photos, here a couple of shots which I hope illustrate the difference well enough to get the point across.






If you have a pre-1914 DWM army Luger and a post-1915 DWM army Luger, pull them out and compare their rear frame well areas--you will see the difference right away.

Call For (More) Data

All this has, of course, prompted some new questions.

Since, according to Walter, the time frame of the two machining changes is so similar, it has occurred to me to wonder if they were instituted simultaneously. I would like to impose on the goodwill and forbearance of everyone who has already responded to the frame spur survey, to re-examine your Lugersâ?? rear frame wells and report serial number and whether they are reinforced or un-reinforced. As usual, please post them or email me [email protected]

Here is the expanded frame well survey. Erfurts are a serious question here, although Walter asserts that all manufacture was reinforced my own 1911 Erfurt is not.

MODEL.......SERIAL#....WELL.....REINFORCE

DWM
1913...........2084ns...spur.........not

1914 LP........262ns...straight
1914............468ns...spur..........not
1914 LP........669ns...straight
1914 LP........696ns...straight
1914 LP........316ns...straight
1914 LP......1339ns...straight
1914 LP......1612ns...straight
1914............1839ns...spur........not
1914...........3440ns...spur........not
1914 LP.......3669ns...straight
1914 LP.......7754ns...straight
1914...........9589ns...spur........not
1914...........9679ns...spur
1914...........3500a...spur........not
1914...........7881a...spur
1914...........8083a...spur
==============================
1914...........9679b...straight.......Y

1915............134ns...straight
1915 LP................straight
1915...........4493a...straight
1915...........1997b...straight
1915...........8413b...straight........Y
1915...........3220c...straight........Y
1915...........5622c...straight........Y
1915...........8202d...straight........Y

1908 Navy...1739b...straight........Y
1908 Navy...1758b...straight
1908 Navy...202xb...straight
1908 Navy...2684b...straight
1908 Navy...3378b...straight
1908 Navy...3509b...straight
1908 Navy...3531b...straight
1908 Navy...3604b...straight
1908 Navy...4895b...straight........Y
1908 Navy...5747b...straight
1908 Navy...5905b...straight
1908 Navy...3392d...straight

P-08 Navy....135....straight......Y


Erfurt
1911................6...spur
1911...........2155...spur
1911...........4517...spur.........not
1911...........6616...spur.........not
1911...........7638...spur.........not
1911...........7686...spur

1911...........8221...straight.....not
1911...........8699...straight

1912............454...straight
1912...........3458...straight.....Y
1912...........9949a...............Y

1914 LP..........50................Y


Commercial
P-08 Comm..46161...spur
P-08 CArmy..68911...spur........not
P-08 CArmy..70149...spur........not
1914 CArmy..70362...spur........Y
1913 C........71368...spur

1914 Comm..72353...straight....Y
1914 Comm..73561...straight
1914 C RG...74200...straight....Y
1914 C RG...74596...straight....Y


As Still notes, 1914 LP-08 production is intermixed with standard P-08 production. A correlation between a corresponding mixture of spring well spur and frame reinforcement would be a strong indication of two frame production streams.

I continue to be most appreciative of everyoneâ??s patience and willingness to take the trouble to take their guns apart and report.

--Dwight

[wlyon]

Dwight. 1914 Commercial 72353. reinforced. 1914 Mil. 1839 . unreinforced. If you need anything else just ask. Bill

[Dwight Gruber]

Bill,

As usual, Johnny-on-the-spot with info, thanks very much. I'll update the posted list soon.

--Dwight

[Dwight Gruber]

Just got a bunch of data from Jan Still's Forum, its a good bite and much food for thought. The table in the top post has been updated and cleaned up a bit, makes it easier to read.

I hope that the folks with the 1914 LP-08s will check their guns for the lanyard reinforcement, also the 1908 Navys. I'm beginning to wonder if LP-08 frames were made on the same line which produced the 1908 Navy frames? Charlie Sorrentino, where is your frame-well mark survey when we need it??

--Dwight

[Jan C Still]

Dwight
I checked my 1917 LP08s. They are all reinforced.
1917 LP08 sn 9937, straight, inner lanyard area reinforced
1917 LP08 sn 1096a, straight, inner lanyard area reinforced
1917 LP08 sn 9868g, straight, inner lanyard area reinforced
1917 LP08 sn 7670f, straight, inner lanyard area reinforced

Information on the 1908 and 1916 and 1917 Navies would be of great interest.
Jan

[Dwight Gruber]

My 1917 Navy is reinforced/no spur.

--Dwight

[Dwight Gruber]

Paolo passed along some frame reinforcement/number data, they have been transcribed into the data list in the first post--thanks very much.

Paolo has also offered a couple of interesting thoughts concerning other modifications surrounding the implementation of the LP-08. When the LP-08 was introduced, the problem had to be solved of making the two guns with different mass firing trains work with the same ammunition--ammuntion altererd to be proper for the LP guns would be too powerful for the standard 4" barrel Luger. Since the ammunition was not changed, some other accommodation needed to be made.

He has observed that a new, weaker recoil spring was instituted along with the LP-08 design: smaller diameter wire and more coils, to allow the LP-08 to function properly. The strengthening of the rear frame was necessary at that point, to counter the heavier impact on it from the rear toggle tail.

He has observed that the difference can be felt in comparing the "feel" of operating the toggle of a pre- and post-1914 Luger. I have checked my Imperial military Lugers for this, and I believe that I can feel the difference, but I don't have very many samples, particularly around the changeover years.

It would be interesting if other correspondents here would check theirs in a similar manner. If anyone will go so far as to check the recoil springs in the first-post data group for spring diameter and number of coils, I will include the information.

Paolo has also suggests checking DWM-manufactured 1906 Swiss Lugers for strengthened rear frames. Since the last Swiss contract was fulfilled mid-1914, a change in frame production might be noted somewhere in the last 1,500 guns of this contract run. If anyone who has Swiss Lugers in the 13701-15215 will check their guns for reinforced rear frames and report them here, I'll add this category to the database. This is beginningto shape up as a potentially revealing aspect of Luger production.

Thanks again to Paolo for these observations, and to everyone else who follows up on this as well.

--Dwight

[Dwight Gruber]

A significant new observation from a NAPCA correspondent puts the change of both the frame spur and frame reinforcement of standard military DWM in 1914 between sn 8083a and 9679b.

--Dwight

[Jan C Still]

Dwight
Is it 8038a or 8083a?
Jan

[Dwight Gruber]

Jan,

Thanks for catching the typo, it is 8083a. Corrected now in all the apporpriate places.

--Dwight

[Jan C Still]

Dwight
1911 Erfurt, sn 8699: straight and Y (reinforced)
Jan