Detective Work: MP-40 mag mystery

I have been collecting MP-40's for about 40 years... back around 1980, I ran across an original MP40 mag that just would not fit into the magazine housing of the MP40's I had in inventory at the time. I ended up selling the mag at a gun show to someone who wanted to create a dummy gun display and he needed to fill his ammo pouches...

After many inquiries, I came across a rumor that during WWII the German's made a quantity of MP-40 magazines (and MP-40's to match???) that would not fit into the magazine well of the standard Wehrmacht WaA MP40. Perhaps they were for export? No one could tell me more on this...

This week I purchased an MP40 mag (code bte42) from a member of this forum... at first I thought it was a counterfeit mag... either someone bought cheap surplus Belgian Verignon mags and re-stamped them with fake WaAmts, or perhaps one of the recent semi-auto/blank gun/dummy gun manufacturers made these mags for their weapons... After all, the mag just looked too good for being 72 years old! And the grinding/filing marks weren't typical of the "milled" MP40 mags we often see.

When I tried to place the bte42 mag into a matching bnz42 MP40 it just wouldn't fit, I compared the bte42 with a bte43 mag that came with the bnz42 MP40 and the markings/funts etc. were so similar that I no longer believe the bte42 to be counterfeit... and then I remembered that old MP40 mag I had years ago!

Speculating some possibilities:
1. The mag was for a part of a WW2 export contract that went with a batch of MP40's
2. The mag was for the MP40/II dual magazine feed weapon (that is unlikely)
3. The mag was for the Wehrmacht PPSH-41 conversion to 9mm that used MP40 mags...
4. The mag was for some other export contract for some 9mm SMG that would use this type of mag.

Any thoughts?

Detective Work Part 2: Photos of bte42 and bte43

bte42 (oversize)
bte43 (fits perfectly)

Well, your theories of being for something else are shot out of the water by the Mp38u40 marking on the side. You say the mag appears unused, or excellent condition- perhaps because it was out of spec and wouldn't fit an MP40! My suggestion is the mag was damaged or just improperly made. There had to have been tolerances for these, and it may be on the high side of tolerance, but too big for any MP40 magwell. Neat to think about though... one other possibility - what if there were mags that were modified for some other type of weapon than the MP40 used by another country (like the Vigeron) after the war? I noticed an extra number stamped on the side.

bte42

I agree with you about the MP38 u 40 on the side marking of the bte42 mag (made around 1942) indicating the mag was made for the Mp38/40 smg.
and yet, the mag also has two inspectors WaffenAmt's... so perhaps this mag, and the one I had years ago were one's that got by the WaA inspectors...

I could understand modification after the war if metal was removed to fit another weapon... or metal was welded on to fit another weapon... but upon close inspection (which the photos don't really show well) this mag has all the factory "finishing" at the same locations (filing or grinding marks) that the other bte43 mag has.

I am leaning toward:
1. Some mags slipped by the inspectors (in spite the alleged rumor as to special batches of mags, the Germans were too obsessive about order and type classification about inspection and WaAmts ...) If the mags were "rejects" they should have followed the same standards of rejection of substandard parts as other WW2 German parts...

2. The mags were issued for a weapon other than the MP38/40... but then why the MP38 u 40 stamping? Why not stamping like "Schmeisser" on MP41 mags?

3. It is (was) not a perfect universe, and sometimes errors are made... especially in war time. Yet... it was 1942 when this mag was made.... I think if it was that out of spec for a standard MP38/40 mag it would have been further "finished" by filing to acceptable dimensions... by some armorer.

4. And what about the numbering on the side? I have seen electropenciled MP40 mags... I do tend to think that was done post-war for some later smg. But what? The Germans wouldn't have been able to plan on making the mags for the post-war Belgians. (Wondering what Verignon mag spec is...?)

I agree with Farb. High cap mags when made by multiple contractors in large numbers for mag wells made by multiple contractors in high numbers are going to have spec issues from time to time. Had the issue with an LMT AR lower (tight end of tolerance) and certain spec AR mags (loose end of tolerance). MP.40 mag wells have more "flex" than the mags. While I wouldn't advise it, if you knocked those mags in there with a mallet (after removing the mag catch which could be damaged) my bet is the mags would fit.

I've shot MP.40s with very loose mag wells that the mags wobbled in which were 100% reliable. Reliability is more a function of feed angle. The biggest issues I've found involved feed lips and follower effect on bullet angle along with ejector fit. I could make those mags run unless quite out of spec/defective. The numbers on the side are postwar showing issue and use IMHO.
The Germans would not have made or designed a weapon or mags practically identical but different spec. Logistics nightmare. They surely would not have marked them for a weapon they were not made for.
Cheers,
HB

bte42 vs. mallet

I tried knocking the mag in with a mallet back in years ago and it took me a LONG while trying to get it out of the mag well.
There is no way that I get expect to get this mag in and out just by knocking it with a mallet. Check the differences in size that I wrote on the postits in photos for the bte42 vs. bte43.
Using a mallet is not going to work.

Hambone said:

I agree with Farb. High cap mags when made by multiple contractors in large numbers for mag wells made by multiple contractors in high numbers are going to have spec issues from time to time. Had the issue with an LMT AR lower (tight end of tolerance) and certain spec AR mags (loose end of tolerance). MP.40 mag wells have more "flex" than the mags. While I wouldn't advise it, if you knocked those mags in there with a mallet (after removing the mag catch which could be damaged) my bet is the mags would fit.

I've shot MP.40s with very loose mag wells that the mags wobbled in which were 100% reliable. Reliability is more a function of feed angle. The biggest issues I've found involved feed lips and follower effect on bullet angle along with ejector fit. I could make those mags run unless quite out of spec/defective. The numbers on the side are postwar showing issue and use IMHO.
The Germans would not have made or designed a weapon or mags practically identical but different spec. Logistics nightmare. They surely would not have marked them for a weapon they were not made for.
Cheers,
HB

Click to expand...

It's a significantly out of spec mag. I would be more surprised at the nonexistence of them than them occasionally turning up. I've probably handled 150 or more different MP.40 mags and the ones that didn't work I made reliable by adjusting the feed lips for follower and cartridge feeding. The numbers on it could mean it was used as a test example for mag wells, such as "go" and "no go" gauges. We have plenty examples of reject K98ks, etc. To think that a small number of the millions of MP.40 mags didn't get made out of spec and find their way to the US is unreasonable.

I had the same experience with a bte 42 marked mag. It was in excellent original condition, but it just would not seat in my all matching f block bnz 41 MP-40. I ended up selling the mag off.

Over the years, I've collected many mags marked 98E 40, 41, 42, and kur 42. These were all made by Steyer, Graz, Austria (WaA815) and they fit and function perfectly. IMHO, they are the best and most consistantly made of the WWII mags. They are just the ticket for use in Steyr guns.

I also have a magazine loader marked ghn 41. I have no doubt that it's original. It simply will not seat on my 98E & kur mags as it's just too small. 98E & kur marked loaders fit and function perfectly, so I've sold off all of the other loaders that got collected over the years.

Makes you wonder what kind of a quality control program was in place during WWII for MP-40 mags and loaders.

FWIW, the Bulgarian loaders that I've seen have been very well made. Marked or unmarked, they are easily spotted by their quality of manufacture and milled solid steel plungers. These usually sell for about $60, and are a nice alternative to pricy originals or repros of questionable quality.