MP28/II vs. MP18I magazines. Differences?

[Mr. Scratch]

So, I've got a semi-auto MP28, and awhile back I purchased a 20-round magazine that din't quite fit in the magazine well. The mag was just a touch too thick. I had it polished down a bit, and it works great now.

Recently I've come across another pair of mags, and same problem. They're just slightly too thick.Both are marked

CAL. 9
DRP SCHMEISSER
70


Looking around on the internets, I've discovered that the MP18 had a run of production that used box mags very much like the MP28, but the mags were ever-so-slightly different, and could be made to work in an MP28.

So, are these actually MP18 mags? And if so, should I not be modifying these to work in my gun?

[Alan Smith]

MP18 box mags use different collar assemblies than MP28 mags; here are a couple of photos to illustrate the different dimensions. The MP18 mag collar has the larger gap between the edge of the collar and the spine of the mag. Is this difference in collar assemblies the cause of the issues you noted?

[Alan Smith]

MP18's originally used the TM08 "drum" type mag; many were (during the Weimar Republic era) converted to use "box" type mags, via use of a new mag well and box-type mags produced by C.G. Haenel.

[JoeW]

Alan, as always, a masterful photo exposition and explanation.

[Alan Smith]

Thanks, Joe - your kind words are appreciated; I hope you and your family are well during these times.

Here are some additional photos to illustrate the differences in MP18 box vs MP28 mags. The first 2 photos are of an MP18 box mag in a Mp28 . . . . no problem as, due to the wider "gap" present on the collar, the MP18 box mag fits in the MP28 just fine. The next 2 photos illustrate a correct MP28 mag in the MP28, just to show how everything is supposed to work. The final photo shows an attempt to insert an MP28 mag into the box mag converted MP18 . . . .clearly a "no go" due to the MP28 mag collar being incompatible with the box mag converted MP18 mag well.

[Alan Smith]

Of Note: I have encountered MP28 mags that were altered to fit into the box mag conversion MP18. In my opinion these are not German military and/or police conversions but, rather, are what we in the US term a "Bubba" job done by a civilian recreational shooter who wanted to be able to use the 32 shot MP28 mag in a box mag converted MP18. By way of example, here is one such "home made" conversion; someone sure spent a lot of time grinding and filing on the MP28 mag to convert it to a use never intended by the original designers and/or end-users in pre-1945 Germany!

[Mr. Scratch]

Well, that was an excellent little photo essay. Thank you for taking the time to do that Alan, and a hat-tip to your photography skills.

So it appears my two 32-round sticks are proper MP28 mags (that just need a bit of adjusting), while the 20-rounder was originally for the MP18.

If I could pick your brain a bit here: did they not make 32-rounders for the MP18? Or 20-round mags for the MP28?

And why did Schmeisser choose to make this design change, instead of just sticking with the original MP18 design and making them fully interchangeable between models?

[Alan Smith]

All I can do is offer observations. To that end, yes - I have seen (but not personally examined) some 32 shot mags for the box mag converted MP18. Below are the seller's photos from a Weimar-era police marked MP18 box mag conversion that I was offered some years ago; I ended up not getting it because I thought the asking price too high. It did eventually sell for the full asking price. In any event, the three (3) 32 shot "Haenel" manufactured box mags that came with it (in an MP40 mag pouch) are the only examples of 32 shot MP18 box mags that I've ever seen or heard of. As to 20 round mags for the MP28, I have no idea, nor do I understand why the MP18 box type & MP28 mags are not interchangeable . . . .you would think that with German military and police being the end-users, such governmental purchasers would have demanded interchangeability of magazines.

[JoeW]

All I can do is offer observations. To that end, yes - I have seen (but not personally examined) some 32 shot mags for the box mag converted MP18. Below are the seller's photos from a Weimar-era police marked MP18 box mag conversion that I was offered some years ago; I ended up not getting it because I thought the asking price too high. It did eventually sell for the full asking price. In any event, the three (3) 32 shot "Haenel" manufactured box mags that came with it (in an MP40 mag pouch) are the only examples of 32 shot MP18 box mags that I've ever seen or heard of. As to 20 round mags for the MP28, I have no idea, nor do I understand why the MP18 box type & MP28 mags are not interchangeable . . . .you would think that with German military and police being the end-users, such governmental purchasers would have demanded interchangeability of magazines.

An article on the MP28II in a 2004 issue of Small Arms Review posited an interesting theory. Schmeisser designed the MP18I which was manufactured by the Bergmann company. He left an allied himself with the Haenel firm. In 1930/31 with Haenel, he designed and patented the stack magazine for submachine guns, producing them in 20 rd versions which he had wanted to provide the German army in 1919 but they refused. With his MP29II design, he used his patented magazines providing them in 32 and 20 versions, but he designed the magazine collars so that they could not be used in the competition's MP18I.bOf course, not only was he selling to the German authorities, but also providing contract sales to other countries.

Apparently, the authors of the article were not aware that 32 round magazines were produced for the MP18I.

The German police in May of 1939, eliminated the use of any 32 round magazines by police forces, requiring them to be returned to the Berlin arsenal with magazine pouches to be exchanged for the 20 round magazine and pouches.

[Alan Smith]

Joe,

That is really interesting about the May, 1939 police directive eliminating use of 32 shot mags. Any idea why this change was made?

Because the MP18 box mags will work in the MP28 (and the German military used the MP28 - on my gun #16177 you can see the small Eagle 37 military acceptance stamp), perhaps the plan was to shift the 32 shot mags to the military for anticipated combat use? The Wehrmacht had an acute shortage of SMG's c. 1939-40, so perhaps the elimination of police use of 32 shot mags was somehow related to working to address the military shortages?

[JoeW]

No documentation why they eliminared the 32 round magazine. Perhaps it was to discourage wastefull fire? Or considering the extra length of the 32 magazine and the resultant extralength of mag pouches, it might be uncomfortable trying to sit in police vehicles during transportation.

[Douglas Jr.]

An article on the MP28II in a 2004 issue of Small Arms Review posited an interesting theory. Schmeisser designed the MP18I which was manufactured by the Bergmann company. He left an allied himself with the Haenel firm. In 1930/31 with Haenel, he designed and patented the stack magazine for submachine guns, producing them in 20 rd versions which he had wanted to provide the German army in 191989 but they refused. With his MP29II design, he used his patented magazines providing them in 32 and 20 versions, but he designed the magazine collars so that they could not be used in the competition's MP18I.bOf course, not only was he selling to the German authorities, but also providing contract sales to other countries.

Apparently, the authors of the article were not aware that 32 round magazines were produced for the MP18I.

The German police in May of 1939, eliminated the use of any 32 round magazines by police forces, requiring them to be returned to the Berlin arsenal with magazine pouches to be exchanged for the 20 round magazine and pouches.

It seems to be an interesting article. The lack of material about the MP28.II is something that bothers me as it was a highly successfull design during the interwar period.
Does the article give any figure abou how many MP28.II were made before the production ceased ?
Douglas

[BasM]

Just a quick introduction: I am Bas Martens from the Netherlands, firearms historian. For a few years now I have been researching the MP 18,I, the MP 28,II, the MP 41 and their copies and competitors, for what is to become a book. There is still quite a lot of material around. As far as known, the MP 28,II was numbered consecutively, the only exception being the Belgian contract guns. Highest serial number I have recorded is 20775, highest serial number I have actually seen and pictured is 19755. So if we take around 21,000 and add 1350 pieces for the Belgian government, that gives a total of approximately 22,350. Production stopped in late 1941 or early 1942.
Those three consecutively numbered 32 round magazines are wonderful. Until these, I had never seen a 32-round magazine for the modified MP 18,I (or a 20-round magazine for the MP 28,II, for that matter). Interestingly, the late production MP 28,IIs have discarded the 'step' in the magazine opening.

[Alan Smith]

Bas,

Welcome to the forum! Your Dutch Lugers book is well-known to collectors here in the US and is an excellent piece of research and presentation on the subject. With that background, I very much look forward to your completion and publication of the work-in-progress book on MP18 + MP28, etc.

When I observed the 32 round Haenel-manufactured box magazines for the converted MP18, I knew they were a bit unusual (specifically, there were the only ones that I had ever seen or heard of). I am, however, quite surprised that you (as a dedicated researcher) have not previously observed them in Europe. Over the years I have regretted not just breaking down and paying the full asking price for the MP18 (#29902 with "S.H.3" Weimar police marking and the 32 shot mags) . . . . oh well . . . that's just the way things go. Just for fun, I'll add a few more of the seller's photos from when this MP18 was offered to me, including the original registration paperwork for the gun (showing it to be a WWII war trophy by a US soldier).

Again, welcome to the forum and we look forward to future contributions from you!

[Promo]

Wow, that is one hell of a beautiful stock! Thank you for sharing the pictures. Also noticed the rare safety it has.