Why fixed loops to hinged loops did not happen in October 1943.

[twthmoses]

I am afraid this is going to be a bit long. Stick around, might be interesting :)

 

Intro.

If you read one of the many books on M1 helmets, that we all love; you will often read a short statement that M1 shells changed from fixed loops to hinged loops in October 1943, sometimes November 1943. Unfortunately there is no further explanation why this is the correct timeframe.

 

I know why October/November 1943 is a reasonable date to assume. It comes from this document “U.S. Army Aberdeen Proving Ground. Test of steel helmets, hinged chinstrap loops for steel helmet, M1. APG-OP-4889-10, Aberdeen Proving Ground, Md., October 1943. Accession Number: AD0498394”.

Sounds very reasonable, testing in October 1943, and McCord starts pumping shells out with these new hinged loops in maybe late October or November. Could surely be true, but is it?

 

Two questions bugged me for a long time. Why there is so few images of hinged loop shells around D-Day + July/August 1944. In addition, are lot stamps sequential produced? Which is a to-folded question. Sequential produced and are there “leftovers” in the stack.

 

Therefore, about three years ago I started my own little project to try to answer these for myself, by systematical recording every single McCord and Schlueter shell I came across, either personal or via the internet. I now have a McCord shell database of around 2500 different lot numbers (plus many duplicates), and about 450 different Schlueter lots. Same time I pick up and read any kind of doc that would illuminate when different lots where produced.

 

To the first question. Does it really take 7-8 months from factory to frontline? Seems unreasonable long. I know; they already had helmets, so only a few replacements would be needed. Something like that seems the common answer. But they also has socks, trousers, shirts, rifles, pistols, tanks, shovels etc., so all this is also made before October 1943? Hmm? New troops from the US arrived after October 1943 in England, some of them must have had hinged loops shells to begin with. We are talking millions of M1 shells produced in this timeframe (oct43-jun44), and very few arrives at the front 7-8 month later? Sounds very strange to me. I will get back to these production numbers later.

 

Are lot stamps sequential produced and are there “leftovers” in the stack? These two questions I can answer relative easy now. There are no leftovers and yes, shells are sequential produced, - pretty much! McCord shells was better sequential produced than Schlueter shells. You cannot say if McCord lot 566A was produced before or after lot 569C, but they are produced within close range of each other – days. Ask this question; why is there no McCord manganese rim shells with lot stamps like 100-200-300-400-500-600-700-800 and most of 900? If there was leftovers in a stack or they are not sequential produced, should there not be? In addition, ask yourself this, what does a lot stamp give of information? It is a shell producer’s representation of the steel manufactures actual heat and lift stamp. With this, you can cross-reference to all kinds of info on the metal used. Good. However, what is the fundamental problem of the M1 shell and has always been, at least for North American shell producers? It is not the metal. Sure many problems in the beginning, and some later on also. The severe deep drawing operation leaves the shell in a highly stressed condition (which is not all bad in fact, subject for another thread). Some break right away and some age-crack (delayed breaking) However, how do you track age cracking - if you draw a few hundred 233C the 14 April, a few hundred 233C the 16 May and so on? You cannot. You take all 2000 some 233C discs and process them on the same day. Giving each lift a specific date. That is the only way you can track age cracking, in that all lifts of a given heat has the same draw date.

 

A database of Lot stamps.

With a database of shell characteristics and lot stamps, it is possible to notice things you do not normal see, by viewing a single shell here and there. There are several trackers on the M1 helmet, for McCord, 1st style and 2nd style fixed loops, C-loops, dimples, hinged loops, low carbon steel loops, rim metal and rear seam. With the exception of low carbon steel loops, C-loops and rim metal, for McCord, all are very sharps changes that happens within roughly 10 lots. These 10 lots are not an indicator of a gradual change of production method, but rather that shells was not 100% sequential produced, like said previously. C-loops exists on a wider range, but still confined to no more than 50 lots or so. This is an indicator that not all C-loops where made at the same time, but made in-between the normal M1 production, just like the M1C production in early 45.

 

Schlueter had fewer trackers, and at first glance, they seem to remain longer in transitions mode. It is a mistake to believe so. While McCord have many lifts to deal with, few in the beginning, many in the middle and large amount in the end, Schlueter does not have that. McCord’s spread in changing shell characteristics displays itself in the lifts, over fewer lots. While Schlueter have both C and extremely rare D lifts, on an unknown number of lots, the spread on changes displays itself mainly in lots. As much as 30-40 lots, extend over some trackers. Further complication it, is the number of discs in each lot. On average, 1943-1945, Schlueter would have around 6200 discs per lot. Unlike Carnegie-Illinois Steel Corp. who poured one gigantic pot of molten iron into an ingot, then subdivided into lifts, Sharon Steel Corp. did it different. Beside one known Carnegie lot, Schlueter used exclusive Sharon steel. Sharon steel Corp. poured from the molten iron pot directly into lifts. Usually 2-3ton each, but also smaller or larger. Therefore, it is hard to say how many discs is in a given lift and how many lifts they poured on a given lot. C and D lifts would end up with many fewer discs, hence its rarity.

 

An extremely rare D lifts of Schlueter.

 

Another thing you can spot in such a database is that a few ranges sports a number of late drawn discs. Two very interesting ranges are McCord lot 95-109 and 970-995. McCord seems to have taken out x number of lifts for some other purpose, and some of them where not used for its intended purpose and entered normal production line again later, thus coming out with later shell characteristics. Example 970-995 sports a number of rear seam and then only a handful for the next 100 lots. There are a couple of other ranges of interest, and there is undoubtful other ranges which will never be noted, because they do not cross a tracker. If we look toward hinged loops, the change is very sharp. Just around McCord lot 793. This does not mean that one lift of lot 795 cannot be fixed loops or one lift in lot 790 cannot be hinged loops, as per stated, nearly sequential produced. For Schlueter the corresponding lot is around 220.

 

Hinged loops.

So what is known of these hinged loops? I do not have the silver bullet document, and sometimes this is not even that good. Take example the document about the rim of the M1 helmet where the Chief of Ordnance is quotes as saying that per 30. September 1944 no more helmets would be produced with stainless steel rim. Well that did not happen! McCord took nearly 200 lots before they pretty much had changed to Manganese rim, but they never did 100%. Schlueter took about a 100 lots to do so, and it seems they did it 100%. None of it happened near October 1944.

Beside the October 1943 doc from Aberdeen Proving Ground, there is an earlier doc, from 17.september 1943 from Watertown Arsenal Lab to the Chief of Ordnance. It concerns the proposed new standard for helmet steel. In this, there is info about the fixed loops. Watertown propose a new loop, something like was used on the test shells from 1941. They also state they are aware that the Detroit Ordnance district office was working on this problem (a new loop) and should be encouraged to finish it and test it.

 

On the other end of the spectrum we know that lot 861H, 863A, 863B, 863C, 864F, 864G and 865G were drawn 10, 11, 15 and 19 July 1944. These shells are all made with hinged loops. So somewhere between the previous paragraph and this, the change occurred. Nothing new here.

 

On 23. December 1943 Watertown Arsenal Lab made a report on defective helmets and discs from the McCord factory. In this report, there is a test of special magnetic U type loops (2nd style fixed McCord loops) made of low carbon steel, welded in place like the normal production line shells. Wording is interesting “used in production”, equal interesting is why would either Watertown or McCord waste time on this project, if shells was already being produced with hinged loops? Neither would. They would, if it had not happened yet. It so happens that McCord was allowed in April 1943 to replace the loops with low carbon steel and at the same time the brass with stamped steel on the chinstraps. The low carbon steel for fixed loops never happened in masses, but, apparently, it was tested as late as December 1943.

 

Schlueter delayed cracking problems.

In early 1944, Schlueter ran into a range of problems with age cracking, primarily around the visor of the shell. It came from December 1943 shipments of shells to the Ordnance department, where up to 4% of the shells had cracked after been approved at the factory, then discovered when received by the different Arsenals. Watertown was quickly instructed to investigate the reason for this age cracking. They found, beside the stress introduced into the metal by the draw that notched in the visor due to defective trimming die, was the main reason. This led Schlueter to run several experimental test on its shells, including carefully ground visor to removed notches or irregularities, and edge-annealed, either via welding or heating. Schlueter did not deliver any M1 shells in January 1944, or the Ordnance Department did not accept any shells from Schlueter in that month. They also started to stamp suffix numbers on the lot stamp, like lot 211B1. This is the machine/stand number, in order to follower, which die draw and trimmed which lot. As far as I know all Schlueter shells from lot 210 to 227 have these suffix numbers.

 

 

One of these Schlueter experiments we know more about. It is lot 213. It is a fixed loop lot. It is spoken about on the second meeting of Helmet Industry Integration Committee held at the production facility of Sharon Steel Corp, the 16-17 march 1944. The experiment was not mentioned on the first meeting, 6-7 march 1944. Schlueter took an entire lot (213) aged them for 15 days, and then recorded the amount of cracked shell. In this case, nearly 50% of all shells was cracked. They then took the uncracked shells and visor edge-annealed, by welding, half of these. The remaining half was unchanged. Aging all of them for another 15 days. So at least 30 days have elapsed before the mention on the 16-17 March meeting. It can be assumed that Lot 213 is an early-to-mid February 1944 produced lot.

Schlueter lot 213.

 

Since the change, in case of Schlueter, from fixed to hinged loop, occurred around lot 220, it can be assumed that lot 220 is a mid to late February 1944 produced lot. Using Schlueter’s production numbers to narrow it down can be difficult in this timeframe. The absent of delivery in January 1944, I am unsure what means. Did Schlueter completely stop production (unlikely), or did delivery cease because of the age experiments Schlueter made? (more likely). Either way Schlueter production numbers are another issue that is way off in most textbooks. The normal two million produced shells listed produced by Schlueter, is too few. Schlueter produced 1.4 mill shells in 1944 alone, and that includes a zero month production (January). The first four month of 1945, they produced an additional 825.000 shells. They were scheduled to produce another 640.000 until end August 1945. Let us just assume they only produced half that. That is combined 2.5 mill shells for 1944 and 1945. To this must be added all of the 1943 production, 199 lots, at least a million, maybe 1.2 - 1.3 mill shells (I do not have Schlueter 1943 numbers). Schlueter production numbers should be listed as more than 3.5 million shells, because this is what they actually produced. On average Schlueter produced 17 lots a month, some month less than 10 lots, others as many as 35 lots.

 

Experimental McCord lot 808.

From McCord we also know of an interesting lot just around the change from fixed to hinged loops. It is the experiment lot 808 made by Carnegie-Illinois Steel Corp. It is a hinged loop shell. The lot is made of a modified Hadfield manganese steel with low carbon (0.80-0.90% instead of 1.20-1.50%) and the addition of 3.5% nickel. 12.000 discs was made into shells in the normal production line. This lot was mentioned at the first meeting of Helmet Industry Integration Committee, 6-7 march 1944. Here it is told the heat is already made and discs from the heat have been shipped to McCord for production into shells. The result is available at the second meeting, 16-17 march 1944. This type of steel gave excellent result, as only 20 of 12.000 discs broke in the manufacturing process.

 

McCord lot 808.

 

A little sidestepping, this modified Hadfield manganese steel or the edge-annealed of the entire circumference of the shell (not just the visor) was the two primary candidate to stress-relieved the edge of a shell, to prevent age cracking. Eventually the Ordnance Department went with edge-annealed using a Tocco high frequency induction-heating unit developed by the Ohio Crankshaft Company. Schlueter installed them almost immediately (around December 1944) while it was made mandatory in February 1945. The new steel standard, AXS-1170, invoked 25. March 1944 also help greatly in creating uniform steel from the Steel companies.

 

Back to McCord lot 808. Knowing that this lot has a draw date between 7-16 March 1944 opens up for some calculations. Lot 865G was made 19 July 1944. That is roughly 57 lots in these four month. In this timeframe, each lot has eight lifts, A, B, C, D, E, F, G and H, each of them on average 2000 discs. McCord should have produced in the vicinity of 912.000 shells in this time (57x8x2000). Looking at the actual production, we find around 992.000 produced shells in this timeframe. (2/3*Mar+Apr+May+Jun+2/3*Jul). Not an exact match. There might be several reasons for this. More lots were made inside the timeframe, the average 2000 discs was exceeded during the period or, as is known, some lots have more that the eight lifts. Example lot 834 has at least 15 lifts (N). However, this is not very common in this timeframe.

 

Doing a little more calculations. There are 15 lots between McCord lot 793 and lot 808. Lot 793 being about the last fixed loop McCord shell, and 794 when hinged loops begins. That is roughly 240.000 shells (15x8x2000). Counting backward from lot 808 we would arrive roughly mid-February 1944 for the production of lot 794. Mccord produced 300k shells in February 1944 and 130k in March 1944. That is very close to when Schlueter started to produce their first hinged loop shells.

 

Actual shell productions is another interesting subject. There is a dip, a radical dip, in production numbers from both McCord and Schlueter just after the assumed mid-late Feb 1944 change to hinged loops. It would take 4 month to get up to the pre-change numbers, with a massive production in the 4Q of 1944. If the change itself is not the very reason for this drop in production, another possibility is the new steels standard for helmets (and body armor) AXS-1170, invoked 25. March 1944. After all its two different manufactures of shells, that has a radical drop in production at the approx. same time. It could of course be the two different steel producers that had problems. Could be interesting to investigate if the same drop was manifested in example body armor for flight personal. If not, I see few reasons why two different manufactures of shells, suffers the same drop, if not for the change to the M1 shell itself.

 

M3 Flak helmet.

The flyer’s helmet M3 is also an indicator that the change occurred later than October-November 1943. M3 shells (and the later M5) have a lot number, just like an M1 shell. Unfortunately when many good people is displaying M3 helmets from their collection (thank you for that), they rarely show the lot stamp, possible unaware that they do have such a number, or, as in many cases the number is partly or fully hidden by the metal band on the shell. The shell is made of the very same discs as the M1 shell. M3 shells was made from December 1943 to February 1945, roughly 210.000 of them. The interesting bit is that some M3 shells have fixed loops and they should not have as they were produced 1-2 month after the supposed change from fixed to hinged loops. However, they do exist. Prototypes, possible? Nevertheless, I think they exist because the change had not happened yet. Less than 3000 were produced in December 1943, and about 170.000 in 1944. A fixed loop M3 shell is rare, and they should be. Before the change from fixed to hinged loops happened, as I think it happened, mid-February 1944, no more than 10-20.000 was produced.

 

D-Day, hinged loops, where are they?

If we assume the change from fixed loops to hinged loops indeed happened in mid-to-late February 1944, as secondary documents support and physical evidence, without explicitly saying so, it becomes very clear why few D-Day+months photos show any hinged loops shells. Only shell production of March and April, which are both low, had any chance of reaching the beaches in time. Hence, few hinged loops shells on photo!

 

Here is a diagram of M1 shells information. More information is available on this diagram than is explained in the above. Some of the information will requires an equal long post to justify. Ask away.

 

[Big Bear]

Dang!!!!!!! Thank you!!!!!

[everforward]

That is a cool chart. Now I will have to get my collection out and see where they fit in the timeline, lol.....

[jmd62]

That's some very impressive research and I love the chart. Thank you!!

[cgutierrez]

WOW!  As an M1 Helmet collector I can't thank you enough.

 

CG

[twthmoses]

On 9/2/2022 at 9:41 PM, everforward said:

That is a cool chart. Now I will have to get my collection out and see where they fit in the timeline, lol.....

I hope they do, or rather i hope you have some that don’t fit the profile. Always on the lookout for shells that are outside the norm. You know, work in progress, more data = better. For 44-45 I love new info on McCord “7” shells, examples of McCord rear seam shells in the 1000 lot range, or of course just one example of a McCord 1300+ shell. On paper they exist. Someone must have one.

[Nickman983]

Very interesting read. Thank you for taking the time to put this all together and share this with the community.

 

What kind of information do you need to help further your database? I'd be more than happy to look through the WWII produced shells in my collection and provide you with information if it might help flush out your research. I took a quick look at my FS stainless steel swivel bail McCords and unfortuantely I can't find a lot number on one of the, the other is 899D but the third is 699A and at a quick look I can't find signs of those bails being done as a repair.

[gitana]

Excellent post. It is nice to see someone support conclusions using data rather than the preponderance of anecdotes. 

Although you've made a lot of suppositions you have provided a lot of good information. 

I assume you've seen this article, but if not it's a great resource. 

https://www.world-war-helmets.com/documentation/USA/M-1/USA_M-1_Helmet_lot_number.pdf

 

 

[twthmoses]

On 9/4/2022 at 6:20 PM, Nickman983 said:

Very interesting read. Thank you for taking the time to put this all together and share this with the community.

 

What kind of information do you need to help further your database? I'd be more than happy to look through the WWII produced shells in my collection and provide you with information if it might help flush out your research. I took a quick look at my FS stainless steel swivel bail McCords and unfortuantely I can't find a lot number on one of the, the other is 899D but the third is 699A and at a quick look I can't find signs of those bails being done as a repair.

Seeing if a hinged loop shell is a former fixed loop shell, can be a bit tricky, especially after around McCord lot 623. However, there are signs. It has been known for many years that fixed loop shells run into the late 700 lots. Lot 699 should be a fixed loop shell. I have 699A on record already and it is a fixed loop.

 

Look at the loops, how they are attached and what metal they are made of.

 

WW2 attached hinged loops, whether factory made or repaired, are attached up to the rim. Sometimes even 1mm on top of the rim, but generally no more than 1-2 mm under the rim. Absolutely, you will find the occasionally “Monday morning” shell with the hinged attached further down and/or very crooked attached. If attached further down, 3-4-5-6 or more mm under the rim, it is a post war attachment (or a post war North American shell)

 

If the metal, either hinge or loop or both, are made of low carbon steel, it is a either a late 1944-1945 factory made shell or a 1945-1946 repair (possible all the way to 1948). Low carbon steel loops/hinges was only manufactured in late 1944-1945, by (or for) McCord.

 

For either of these things, it does not matter if you have sewn on chinstraps; they were sewn on all the way to 1950 by the different arsenals that made repair to the shells.

 

What really gives it away is the outside. Unfortunately is can be obscured by paint and especially texture. Can be very hard to see, but look closely. You will see the marks from the spot weld, for both the original fixed loop and the new hinged loop.

 

 

Not just original fixed loop shells was repaired with hinged loop. Before the hinged loop was invented, shells also broke. This is a fixed loop shell, repaired with a new fixed loop. Ever wondered why C-loops always seems to be brazed? However, where are all the brazed normal fixed loop shells? There should be a magnitude more of them?!

 

[twthmoses]

On 9/4/2022 at 9:33 PM, gitana said:

Excellent post. It is nice to see someone support conclusions using data rather than the preponderance of anecdotes. 

Although you've made a lot of suppositions you have provided a lot of good information. 

I assume you've seen this article, but if not it's a great resource. 

https://www.world-war-helmets.com/documentation/USA/M-1/USA_M-1_Helmet_lot_number.pdf

 

 

 

Yes i have seen it. A really good read, with lots of good information.

[Nickman983]

Thanks for sharing that information. The guy who did the repair on mine must have been on his A game as the other fixed fails converted to swivel bails I have in my collection are fairly obvious and still show signs of their previous fixed bail. There's no obvious sanding where the old bails used to be and I can't make out the old spot weld marks on the outside but the loops themselves are not stainless.

[twthmoses]

On 9/8/2022 at 10:19 PM, Nickman983 said:

Thanks for sharing that information. The guy who did the repair on mine must have been on his A game as the other fixed fails converted to swivel bails I have in my collection are fairly obvious and still show signs of their previous fixed bail. There's no obvious sanding where the old bails used to be and I can't make out the old spot weld marks on the outside but the loops themselves are not stainless.

If you could post images, it would be great. Always on the lookout for new info. Maybe you got something special. Happens all the time. Always new stuff to learn. Have yet to see a lift factory made with both fixed and hinged loops. 

[Nickman983]

Here's the one in question

 

And here's another one I have that I'm pretty confident is a repair

[twthmoses]

On 9/13/2022 at 6:16 PM, Nickman983 said:

Here's the one in question

 

And here's another one I have that I'm pretty confident is a repair

 

Thanks for good images.

 

The 699A shell is a former fixed loop shell.

The loop ring are low carbon steel, which would give it a manufacturing date of late 44 or 45. If it is a repair, which this is, it will give it a repair date of 45-46. The hinged loops are attached up to the rim, just as it should be for this date range. You can see the three spot weld from the new-attached hinged loops, very clear on one side, not so clear on the other side, of the shell. The shell has not been repainted this is why you can see them. The texture/paint around the weld area is not sufficient worn down to clearly spot the original fixed loops weld, but the left and right spot weld appears larger, and is probably a mix of the original and new. Nearly on top of each other.

 

The other looks like a 674D. Nice, do not have a 674D on record.

This should also be a former fixed loop shell. I cannot say for certain, because it cannot see it. The attached hinged loops indicates it is a postwar repair. They are not attached up to the rim, neither of them. It has a second layer of paint that prevents seeing the three new spot weld on the outside - just as the original paint prevents seeing the original weld. If you ever removed the paint, one or both layers, I am sure you would see the spots weld from both the original and new loops. A difficult one for sure.