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Here at Sturgeon's House, we do not shy from the wholesale slaughter of sacred cows.  That is, of course, provided that they deserve to be slaughtered.

 

The discipline of Military Science has, perhaps unavoidably, created a number of "paper tigers," weapons that are theoretically attractive, but really fail to work in reality.  War is a dangerous sort of activity, so most of the discussion of it must, perforce, remain theoretical.  Theory and reality will at some point inevitably diverge, and this creates some heartaches for some people.  Terminal, in some cases, such as all those American bomber crews who could never complete a tour of duty over Fortress Europe because the pre-war planners had been completely convinced that the defensive armament of the bombers would be sufficient to see them through.

 

In other cases though, the paper tiger is created post-facto, through the repetition of sloppy research without consulting the primary documents.  One of the best examples of a paper tiger is the Tiger tank, a design which you would think was nearly invincible in combat from reading the modern hype of it, but in fact could be fairly easily seen off by 75mm armed Shermans, and occasionally killed by scout vehicles.  Add to this chronic, never-solved reliability problems, outrageous production costs, and absurd maintenance demands (ten hours to change a single road wheel?), and you have a tank that really just wasn't very good.

 

And so it is time to set the record straight on another historical design whose legend has outgrown its actual merit, the British EM-2:

 

AYqxSeZ.jpg

 

EM-2ology is a sadly under-developed field of study for gun nerds.  There is no authoritative book on the history and design of this rifle.  Yes, I am aware of the Collector's Grade book on the subject.  I've actually read it and it isn't very good.  It isn't very long, and it is quite poorly edited, among other sins devoting several pages to reproducing J.B.S. Haldane's essay On Being the Right Size in full.  Why?!!?!!

 

On top of that, there's quite a bit of misinformation that gets repeated as gospel.  Hopefully, this thread can serve as a collection point for proper scholarship on this interesting, but bad design.

 

Question One:  Why do you say that the EM-2 was bad?  Is it because you're an American, and you love trashing everything that comes out of Airstrip One?  Why won't America love us?  We gave you your language!  PLEASE LOVE ME!  I AM SO LONELY NOW THAT I TOLD THE ENTIRE REST OF EUROPE TO FUCK OFF.

 

 

Answer:  I'm saying the EM-2 was a bad design because it was a bad design.  Same as British tanks, really.  You lot design decent airplanes, but please leave the tanks, rifles and dentistry to the global superpower across the pond that owns you body and soul.  Oh, and leave cars to the Japanese.  To be honest, Americans can't do those right either.

 

No, I'm not going to launch into some stupid tirade about how all bullpup assault rifle designs are inherently a poor idea.  I would agree with the statement that all such designs have so far been poorly executed, but frankly, very few assault rifles that aren't the AR-15 or AK are worth a damn, so that's hardly surprising.  In fact, the length savings that a bullpup design provides are very attractive provided that the designer takes the ergonomic challenges into consideration (and this the EM-2 designers did, with some unique solutions).

 

Actually, there were two problems with the EM-2, and neither had anything to do with being a bullpup.  The first problem is that it didn't fucking work, and the second problem is that there was absolutely no way the EM-2 could have been mass-produced without completely re-thinking the design.

 

See this test record for exhaustive documentation of the fact that the EM-2 did not work.  Points of note:

 

-In less than ten thousand rounds the headspace of two of the EM-2s increased by .009 and .012 inches.  That is an order of magnitude larger than what is usually considered safe tolerances for headspace.

 

-The EM-2 was less reliable than an M1 Garand.  Note that, contrary to popular assertion, the EM-2 was not particularly reliable in dust.  It was just less unreliable in dust than the other two designs, and that all three were less reliable than an M1 Garand.

 

-The EM-2 was shockingly inaccurate with the ammunition provided and shot 14 MOA at 100 yards.  Seriously, look it up, that's what the test says.  There are clapped-out AKs buried for years in the Laotian jungle that shoot better than that.

 

-The EM-2 had more parts breakages than any other rifle tested.

 

-The EM-2 had more parts than any other rifle tested.

 

-The fact that the EM-2 had a high bolt carrier velocity and problems with light primer strikes in full auto suggests it was suffering from bolt carrier bounce.

 

 

As for the gun being completely un-suited to mass production, watch this video:

 

 

 

Question Two:  But the EM-2 could have been developed into a good weapon system if the meanie-head Yanks hadn't insisted on the 7.62x51mm cartridge, which was too large and powerful for the EM-2 to handle!

 

Anyone who repeats this one is ignorant of how bolt thrust works, and has done zero research on the EM-2.  In other words, anyone who says this is stupid and should feel bad for being stupid.  The maximum force exerted on the bolt of a firearm is the peak pressure multiplied by the interior area of the cartridge case.  You know, like you'd expect given the dimensional identities of force, area and pressure, if you were the sort of person who could do basic dimensional analysis, i.e. not a stupid one.

 

Later version of the British 7mm cartridge had the same case head diameter as the 7.62x51mm NATO, so converting the design to fire the larger ammunition was not only possible but was actually done.  In fact, most the EM-2s made were in 7.62x51mm.  It was even possible to chamber the EM-2 in .30-06.

 

I'm not going to say that this was because the basic action was strong enough to handle the 7x43mm, and therefore also strong enough to handle the 7.62x51mm NATO, because the headspace problems encountered in the 1950 test show that it really wasn't up to snuff with the weaker ammunition.  But I think it's fair to say that the EM-2 was roughly equally as capable of bashing itself to pieces in 7mm, 7.62 NATO or .30-06 flavor.

 

 

Question Three:  You're being mean and intentionally provocative.  Didn't you say that there were some good things about the design?

 

I did imply that there were some good aspects of the design, but I was lying.  Actually, there's only one good idea in the entire design.  But it's a really good idea, and I'm actually surprised that nobody has copied it.

 

If you look at the patent, you can see that the magazine catch is extremely complicated.  However, per the US Army test report the magazine and magazine catch design were robust and reliable.

 

What makes the EM-2 special is how the bolt behaves during a reload.  Like many rifles, the EM-2 has a tab on the magazine follower that pushes up the bolt catch in the receiver.  This locks the bolt open after the last shot, which helps to inform the soldier that the rifle is empty.  This part is nothing special; AR-15s, SKSs, FALs and many other rifles do this.

 

What is special is what happens when a fresh magazine is inserted.  There is an additional lever in each magazine that is pushed by the magazine follower when the follower is in the top position of the magazine.  This lever will trip the bolt catch of the rifle provided that the follower is not in the top position; i.e. if the magazine has any ammunition in it.

 

This means that the reload drill for an EM-2 is to fire the rifle until it is empty and the bolt locks back, then pull out the empty magazine, and put in a fresh one.  That's it; no fussing with the charging handle, no hitting a bolt release.  When the first magazine runs empty the bolt gets locked open, and as soon as a loaded one is inserted the bolt closes itself again.  This is a very good solution to the problem of fast reloads in a bullpup (or any other firearm).  It's so clever that I'm actually surprised that nobody has copied it.

 

Question Four:  But what about the intermediate cartridge the EM-2 fired?  Doesn't that represent a lost opportunity vis a vis the too powerful 7.62 NATO?

 

Sort of, but not really.  The 7mm ammunition the EM-2 fired went through several iterations, becoming increasingly powerful.  The earliest versions of the 7mm ammunition had similar ballistics to Soviet 7.62x39mm, while the last versions were only a hair less powerful than 7.62x51mm NATO.

 

As for the 7mm ammunition having some optimum balance between weight, recoil and trajectory, I'm skeptical.  The bullets the 7mm cartridges used were not particularly aerodynamic, so while they enjoyed good sectional density and (in the earlier stages) moderate recoil, it's not like they were getting everything they could have out of the design.

 

220px-280_30_British_Ammunition.jpg

note the flat base

 

In addition, the .280 ammunition was miserably inaccurate.  Check the US rifle tests; the .280 chambered proto-FAL couldn't hit anything either.

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Correction of the record, the .280/30 dates to 1948 off the top of my head, so it wasn't "later variants", it was "virtually all of the ammunition and weapons actually produced", with only a handful of Mann barrels and maybe one or two FALs as the exception chambered in the original .280

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There's quite a bit more to add to SH's only unironic bash thread. Some excerpts from things I've written, starting with the Modern Intermediate Calibers episode on the .280:

 

Well, although the .280 is not a poor design by any means, under bright exam table lights it withers a little bit against its stellar reputation. That reputation, and exactly how and why I think it’s not quite deserved, are why I am taking the time to do an extended-length post on the subject. Before we get into that, though, we need to understand what we are really talking about: Chiefly, that the .280 British isn’t just one round, but several. I am not going to get into the history of the round here, because I have a much larger, more detailed post on the subject in the works as part of my series on the US Lightweight Rifle program that resulted in the M14, but let’s take a quick look at some of the different performance variations of the .280 round:

  • Early .280 ammunition used a unique 0.458″ diameter case head, and tests in the last quarter of 1949 showed that it propelled a 130gr steel-cored bullet at 2,270 ft/s from a 24″ barrel. This represents the least powerful .280 round developed.
  • At the same time, 140gr bullets were being loaded in .280 cases by both FN in Belgium and in the UK. Notes from the period cite a muzzle velocity of 2,330 ft/s from a 24″ barrel for rounds of this type.
  • To ease development, the .280 was changed in 1949 to use the same rim dimensions and 0.473″ diameter case head of the US .30 Light Rifle cartridge (which became 7.62 NATO). This variant was called .280/30, and its performance varied depending on the exact propellant and barrel length used. However, for a brief time the objective for this round was a velocity of 2,415 ft/s from a 24″ barrel with a 140gr steel-cored bullet.
  • At the end of 1950, the British augmented the performance of the .280/30 by loading a lower-drag 140gr FN S-12 flat-based lead-cored projectile into the case, and firing it at a higher velocity of 2,595 ft/s*. It was this load that was briefly adopted as the 7mm Mk.1Z in 1951 before the program was dropped two and a half years later. *It should be noted that tests from 1952 list the muzzle velocity of this round as 2,660 ft/s, so the 2,595 ft/s figure may be an instrumental velocity.

...

OK, so with all that done, what do we make of this British .280 caliber? Well, it’s not a bad round. In fact, in a strictly technical sense, I would say it probably was the better concept, versus the American .30 caliber that became 7.62 NATO. However, it seems to me that conflation of the early, more sedate loads, and the later high-performance ones has given many the impression that the .280 was some kind of wonder-round that could do everything and at the same time kicked like a kitten. That is not true.

Should the .280 have been adopted? No, I don’t think so. Although the round was conceptually superior to the American .30 T65, British development of the round experienced significant and lingering problems. The caliber was plagued by poor accuracy when loaded with British steel-cored bullets, and the Belgian S-12 projectile, although relatively low drag and possessing generally excellent characteristics, lacked the ability to penetrate steel helmets beyond 700 meters. In addition, the more heavily arced trajectory of the .280 was never fully ameliorated, except by even larger and more powerful abortive 7mm variants of the American .30 caliber. For these reasons, the American, French, and Canadian delegates to NATO expressed their preference for the .30 T65, and even the British delegates did not commit fully to the .280, instead suggesting the Organization adopt both. Had the Americans embraced the .280 concept and injected more funding and manpower into the effort, maybe it could have succeeded, but even by 1949, when the .280 was still in its infancy, the .30 T65 was already nearly perfected, having had a three-year head start on the British effort. NATO had no reason to choose a less developed, riskier caliber, and the pressure to standardize at all costs was high. Although the choice of the .30 T65 is disappointing to those of us who wonder what could have been, at the time it was probably the right one.

Two short articles I did on the .280 and NATO rifle competitions:

http://www.thefirearmblog.com/blog/2016/02/28/the-return-of-weekly-dtic/

 

http://www.thefirearmblog.com/blog/2015/01/28/rifle-competition-us-vs-uk-1950-dtic/

 

Something from my notes for Light Rifle V - coming soon™:

 

.280 Lead Issue:

http://digicoll.library.wisc.edu/cgi-bin/EcoNatRes/EcoNatRes-idx?type=article&did=EcoNatRes.MinYB1951.PDettmer&id=EcoNatRes.MinYB1951&isize=text

http://images.library.wisc.edu/EcoNatRes/EFacs2/MineralsYearBk/MinYB1951/reference/econatres.minyb1951.obishop.pdf

http://images.library.wisc.edu/EcoNatRes/EFacs2/MineralsYearBk/MinYB1951/reference/econatres.minyb1951.pdettmer.pdf

http://www.alu.army.mil/alog/issues/SepOct10/spectrum_smallarms_ammo.html

http://forums.delphiforums.com/autogun/messages/?msg=6772.5

So, I don't know the exact answer, but I think I can speculate with reasonable accuracy. If one looks at yearly ammunition production in the post war era, even during wartime, we are talking roughly a billion to two billion rounds per year, of 5.56, 7.62, and .50 cal.

World War II was considerably more intensive: Annual requirements were over 21 billion rounds. Given the scale of World War I and World War II, the US must have believe that a war with Russia would have been at least on that scale, if not larger. There is about 6.8 grams of lead in each S-12 140gr bullet. Times 21.6 billion, that means annual lead production would have to be at least 147 million kilograms, or 0.15 million metric tonnes per year reserved solely for S-12 production. In 1951, 76,713 tons (I assume US tons, so 69,579 tonnes) of lead were produced in the US. I don't have a good idea what reserves were, but you can see that in terms of annual production the US had less than half as much lead as it needed to produce the S-12 bullet in those quantities.

And keep in mind, as well, that the S-12 bullet was the only bullet that was at the time proven to be successful in the .280.

Jochem, thanks a lot for asking this question. This was an angle I hadn't considered, and it will definitely be going into my coverage of the matter.

*EDIT 11/6/2016: Looks like this is production for Idaho, although total US production isn't a lot better. Resources for Freedom quotes that less than 400,000 tons of lead were being produced domestically by the late Forties, and 1951 was a "lead drought" year, with only 388,000 tonnes of lead produced domestically. So adopting S-12 would have required something like 38% of domestic lead mine production annually during a "world war" year to be devoted to that bullet alone. The US just couldn't afford this, as the demands for lead in other sectors were increasing, and supply decreasing. In the 1950s onward, there were efforts ongoing in all lead-use sectors to "unlead" lead-using products, but by 1975, Resources for Freedom was predicting that there would be little or no further progress here, and the lead deficit was still getting worse.

As long as production of ammunition was subdued to normal "brush war" levels at a billion or two rounds per year, a lead-cored bullet wouldn't be a problem. Indeed, the difficulty of manufacturing M59 Ball would result in the development of lead-cored M80, but M59 was always considered the design that would be used in the event of a large-scale conflict.

Lead shortage 1940s and 1950s:

https://books.google.com/books?id=OOMfAAAAMAAJ&lpg=PA249&ots=7Bvk6OSsUG&dq=us%20metal%20stockpiles%201950&pg=PA239#v=onepage&q&f=false

http://images.library.wisc.edu/EcoNatRes/EFacs2/MineralsYearBk/MinYB1951/reference/econatres.minyb1951.obishop.pdf

565,000 tons of lead imported in 1950

Use of lead by the US in 1950 was greater than in any other year, including years of WWII

In 1950, 30 percent of lead came from domestic mine production, 30 percent from scrap, and 40 percent from imports.

Development of reserves proved inadequate to offset depletion.

Tetraethyl lead in gasoline rose from negligible, to one tenth of lead consumption by the late Forties. This problem was only going to get worse, not better.

Lead mine production declined from 1925 to 1950, from 684,000 tons annually to less than 400,000 tonnes annually by the late 1940s.

https://babel.hathitrust.org/cgi/pt/search?q1=lead%20shortage;id=mdp.39015027399834;view=1up;seq=9;start=1;sz=10;page=search;orient=0

https://babel.hathitrust.org/cgi/pt?id=osu.32435015817760;view=1up;seq=11

 

46RoCl1.png This table from page 39 of Resources for Freedom illustrates lead usage in the United States in 1950. Note that well over 73% of lead is consumed by non-small arms uses.

 

I have never handled an EM-2, but I know four or five people who have not only handled examples, but disassembled them (Those being: Ian McCollum, Matt Moss, Jonathan Ferguson, Trevor Weston, and maybe one or two others I correspond with). It's worth noting that at least three of those people believe that the EM-2 could not have been mass produced economically in the configuration of the test rifles - the receiver was simply too big and complex a workpiece.

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Question Five: BUT DA GERPERSCHEERSSSSS!!!!

 

 

Sturgeon talked me through some of the history of the .280 British cartridge, which is something he's researched quite a bit.

 

One of the ideas that's become a trendy topic of discussion lately is the idea of a General Purpose Cartridge, (GPC), which would be a sort of half-way house between 5.56 NATO and 7.62 NATO that would replace both.  This is logistically attractive, but making a cartridge that can comfortably replace both existing cartridges isn't easy.

 

The merits and demerits of the GPC idea are beyond the scope of this thread.  However, the .280 British is often brought up as an approximation of what a GPC would look like, and this simply isn't historical.

 

The original British plan was to retain the .303 Vickers belt-fed machine gun, but to supplement it at squad level with a new machine gun design in .280 called the TADEN (which was a sort of belt-fed Bren derivative with spade grips):

 

pIUz2dI.jpg

 

The US, meanwhile, insisted on a single cartridge solution (also, nobody but the British and Commonwealth used .303), and that was part of the impetus for making the .280 more powerful.  Once the .280 was made powerful enough to satisfy the trajectory requirements, it really wasn't an assault rifle cartridge anymore, as it produced only a little less recoil than 7.62 NATO.

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Yeah, .280 was never realistically going to be a GPC the way Tony imagines (for those who don't know, Anthony Williams cites the .280 explicitly as an example of a "GPC that might have been"). It's weird, too, because it's not like Tony doesn't know a lot about the .280's history. I think the guy really does just have his blinders on.

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Here are some less-seen pictures of the EM-2:

 

gJiJM92.jpg

 

"Brigadier Lindsay of the British Army presented an EM2 rifle to the Springfield Armory Benton Small Arms Museum"

 

CGDX9BQ.jpg

 

A field-stripped view of the EM-2.  You can see the extra lobe on the back of the magazine that houses the automatic bolt closure mechanism.

 

hadCbvN.jpg

 

EM-2 and STG-44.  Just chilling.

 

ed9T5Ki.jpg

 

Size comparison of the EM-2 carbine variant, a regular EM-2 and a proto-FAL

 

sT112cQ.jpg

 

An early(?) EM-2, then called the "Mamba."  Note the different sight and handguard.

 

Y2ku7M0.jpg

 

Not an EM-2, but an EM-1, which was called the "Cobra."

 

More EM-2 goodness

 

A whole mess of EM-2 porn

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I believe that it's a one-power sight.  The scope body is shaped to try and match the angle of light entering the eye with a typical soldier's eye position; the shooter should see the scope body almost edge on, and it should occlude as little of their view as possible.

Essentially, they were trying to accomplish the same thing as a red dot sight does.

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There are a few things to note about the Cody Museum's EM-2:

-As Sturge notes in his blurbette on TFB, this is a later 7.62x51mm weapon.

-The charging handle is coated with bakelite, which is something I have not seen in other pictures of EM-2s.  One of the complaints that was raised in the US trials was that the charging handle of the EM-2 tended to burn the user.  It's likely that the bakelite coating is an attempt to rectify this.

-I was totally going to try and field strip this sucker to get a look at the internals, and when we were asking for permission to do so, we were told that there was a gigantic blizzard incoming and everyone had to leave the museum.  In a display of excellent judgment, Sturgeon and I then decided to start driving on the highway for Montana.

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Further Further notes on the Cody Museum's EM-2:

 

-There were, discounting the first five hand-built prototypes, there were four batches of EM-2s built.

 

-The first twenty rifles were made in the .280 caliber.  These rifles were made by Chambons Tool Company as well as RSAF Enfield.  These were the weapons used in the American competitive trials against the T25 and early FAL prototype in 1950.  Even at this early date, these rifles were considered "semi-production," i.e. aside from small tweaks, the design was already frozen.

 

-A further batch of six rifles was made by BSA in 1951-1952 in the .300 T65 caliber.  These also incorporated small changes based on experience from the American trials.

 

-Another batch of fourteen rifles was made by RSAF Enfield in the finalized 7.62x51mm NATO cartridge.  The Cody Museum's rifle is number nine from this batch of fourteen.  It does not appear that these rifles were subjected to much testing.  This is also the configuration of the rifle that was "adopted" by the War Office as Rifle Number 9.  If Winston Churchill had gotten completely pissed and forgotten to rescind the Labor government's idiotic order that the EM-2 be adopted, the rifle would have been adopted in 7.62x51mm, not .280!

 

-Oddly enough, the politicians did not seem to be aware of this fact.  There was intense political debate on the merits of Britain adopting their own .280 ammunition vs. the American 300 caliber, but by the time this debate was held the EM-2 had already been re-designed for .300 caliber ammunition!

 

-A final ten rifles were made in Canada by Canadian Arsenals Limited in 7mm Compromise (7x51mm) before the entire EM-2 program was cancelled in 1953.

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Question Six: Why was this thing so poorly suited for mass-production?

 

 

Let's look at the problems of mass-producing small arms in a little more detail.
 

0Kr5LQv.jpg?1

Can you tell it from a javelin?

 

This is the receiver of a Mauser Gewehr 98/K98 rifle.  The receiver is responsible for containing the force of the burning propellant, which for a few ten-thousandths of a second is on the order of four tons.  The receiver thus needs to be quite strong, and along with the barrel it is the single most expensive portion of the rifle.

 

The receiver of the Mauser rifle is made of a forging of ordnance-grade steel.  This means that a billet of steel is heated until it is soft, but not molten, and then mashed in some gigantic mechanical hammers into a rough outline of the final shape like so:

 

Pgzhe9f.jpg?1

 

After that the forging must be machined or milled.  In this step, various machine cutting tools are used to remove excess material.

 

6vkf9Qd.jpg

 

The Mauser is generally held to be the best-engineered of the First World War rifles, but all other rifles from the period were of comparable construction.

 

During the First World War, all major combatants found out that their rifles were simply too damned expensive.  War planning had assumed that the next conflict would involve far fewer soldiers than it actually did, and planners had failed to anticipate the number of rifles that were lost or destroyed in the field.  All major combatants in the First World War learned this painful lesson, but to the Germans the problem was especially dire, as they were heavily reliant on foreign supplies of the alloys for making ordnance-grade steel.  To the Germans, reducing the amount of specialized alloys used in their rifles was a major strategic issue.  Most other nations had more reliable supplies of alloy raw materials, but reducing the cost of weapons and time needed to produce weapons was still a major concern, once the tempo and scale of modern warfare was understood.

 

The German solution was the STG-44, née MKb-42(H), which was the culmination of research into cheaper weapons that had been started in the 1930s.  The designers had realized that there really wasn't any way to make the barrel cheaper, but they could make the receiver substantially cheaper.  The STG-44 achieves the remarkable feat of having no ordnance-grade steel in the receiver whatsoever.  Additionally, much of the rest of the receiver was made of stampings.  Stampings are steel components made of sheet metal that is bent, cut and formed with hydraulic presses and dies.  Stampings are not only faster and cheaper to make than machined forgings (at least for large production runs, for smaller runs they are less economical), but they produce far less waste material that needs to be recycled.  Production volume can be increased enormously.  The changeover from the milled-receiver PPSh-41 to the stamped PPS-43 [Sturgeon edit: The PPSh-41 has a stamped receiver. I am not sure whether colli intended to say "PPD-40" (which was milled) and "PPSh-41", or something else]* allowed the Soviet Union to double the number of SMGs made per month during WWII.

 

hG90lFB.jpg

An STG-44 receiver stamping

 

Most post-war small arms development focused on the use of stampings.  The Soviets had the greatest success: the AKM was a truly sublime piece of manufacturing engineering.  Western designers took a little longer to figure things out; of the first generation of Western combat rifles, only the CETME/G3 had a stamped receiver (though there were many stamped prototypes that simply didn't make it).  Also, the receiver stamping of the CETME/G3 is quite a lot more complex than that of the AK, and it is also heavier.  Still, while it failed to meet the high standard for production streamlining that the AKM achieved, it was a perfectly competent effort for the era.

 

nFt1bIk.jpg?1

And HK G3, showing some of the stages of turning raw sheet metal into the finished rifle.  Stamping the receiver of an HK rifle is a complex, multi-step process.

 

All that said, the milled Western rifles weren't completely hopeless.  While the use of a milled receiver in the FAL and the M14 was basically backwards and primitive by the 1950s, both of these rifles have reasonably small receivers.  So, while the steel still needs to be removed from the forging by the lengthy and laborious process of milling it off chip by chip, the total amount of milling that has to be done isn't that great:

 

1m5g2su.png

In the FAL the receiver is kept compact in part because some of the moving parts are housed in the stock.

 

lJ0Gz7l.jpg?1

In the M14 the receiver is kept compact because many of the moving parts are outside of the receiver.  However, this makes them vulnerable to mud and dust.

 

At the same time, a private firm spun off from an aerospace company called Armalite had a different idea.  They constructed their rifle, the AR-10 primarily out of aerospace-grade aluminum and used an absolute minimum of high-grade steel where needed for strength.  Aluminum alloys have a higher strength-to-weight ratio than steel stampings, but in addition to saving weight, they solved the manufacturing problem as well.  Aluminum alloys, while more expensive than steel, were not in short or tenuous supply for any major power after World War Two, so they were unlikely to become a chokepoint for rifle production.  In addition, aluminum is much softer than steel, which permits much faster machining operations.  Thus, the aluminum receiver of the AR-10, while conventionally machined from a forging just like the rifles of the previous generation, did represent a viable alternative to sheet steel stampings for mass production.

 

Mass production is addressed at 3:28

 

So, you want to know what post-war combat rifle was designed without any thought of streamlined mass production whatsoever?  Yep, that's right, the EM-2.

 

6zxUEkr.jpg

 

Per the official records, the rifle was 35 inches long and had a 24.5 inch barrel.  The last inch or so (generously) of the rifle consisted of the buttpad.  However, we can also see that at least an inch and a half of receiver wrapped around the barrel past the bolt face:

 

jx5WYld.jpg

 

So, the receiver of the EM-2 is at least eleven inches long.  The receiver of the FAL and M14 were both about eight inches long.  On top of that, the receiver of the EM-2 was much larger and voluminous than that of the FAL or the M14, as it completely encloses the bolt carrier and bolt carrier raceways and return spring, which is not the case in either of those designs.

 

An enormous amount of maching time would be spent in particular on the rear portion of the receiver, which is a large, hollow area where the bolt carrier reciprocates.  Much material would need to be removed here, and that would take a large amount of machine time.  Furthermore, this would be hard, expensive, ordnance-grade steel.

 

There is no indication whatsoever that this expensive, time-consuming receiver was ever considered an interim design.  Indeed, Enfield had already made arrangements with outside contractors to heat treat the gigantic receiver, as they apparently lacked the capacity to do so.  The .280 trial models sent to the US for competitive testing were considered "semi-production," and the changes made after the 1950 US trials were extremely minor and did not involve changing the construction of the receiver.

 

Interestingly, there is a British document from 1951 that acknowledges that the EM-2 was more expensive to produce than the FAL.  It then proceeds to give a variety of silly excuses for why this is the case (e.g. that it was made to higher standards and was intended to be accurate enough to double as a sniper rifle, and that front-locking weapons are inherently more expensive to make).  However, this document declines to give exact costs.

 

It is clear, however, that the EM-2 was really very poorly suited to mass production.

 

 

 

*The anecdote about the PPS-43 vs the PPSh-41 is taken directly from the Collector's Grade book on the STG-44.  As Sturgeon points out, the PPSh-41 is also stamped, so I have no idea WTF they are actually talking about.  Possibly the PPS-43 was simply better production optimized.

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4 hours ago, Collimatrix said:

 

-Another batch of fourteen rifles was made by RSAF Enfield in the finalized 7.62x51mm NATO cartridge.  The Cody Museum's rifle is number nine from this batch of fourteen.  It does not appear that these rifles were subjected to much testing.  This is also the configuration of the rifle that was "adopted" by the War Office as Rifle Number 9.  If Winston Churchill had gotten completely pissed and forgotten to rescind the Labor government's idiotic order that the EM-2 be adopted, the rifle would have been adopted in 7.62x51mm, not .280!

 

Whoah whoah, citation please? They standardized the .280 as the 7mm Mk. 1Z at the same time, so I am not at all convinced that just because the pattern from that batch was adopted as Rifle No. 9 that means they would have been in 7.62mm.

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I'm going to take minor issue with the part of your thesis that characterizes US production as behind because it focused on forging the receivers. I say this, because the US had gotten extremely good at receiver forgings. You show an image of "M14" receiver production which is highly misleading, as it is in fact an image of the modern Smith Enterprises Inc machining process (from billet) of their M14 reproduction receivers. In reality, the M14 receive was formed from a very close forging. For comparison, here are some images of an original M1 forging:

 

DSC_1973s.jpg

DSC_1971s.jpg

springfield-armory-m14-receiver-forged.j

 

This receiver forging obviously required additional machining to turn it into the finished product, but you can see the level of extreme detail conveyed to the blank by the forge: Even the cutout for the rear sight mechanism, and the feed area are forged straight into the receiver. As well, the details on the underside of the receiver are already beginning to show, such as the hollow where the bolt reciprocates, and the area for the magazine.

 

These forgings lost very little mass to become finished receivers, relative to what other forgings require (compare to the FAL receiver in your post above). In this way, they were extremely well production optimized.

 

Of course, it's true that the receivers still took some considerable machine time to finish (though much less than other forgings), and there were correspondingly efforts to reduce the cost of the weapons. Although M14 manufacturer Harrington and Richardson decided to make their rifles exactly the same way they were making M1s, Winchester and TRW both innovated new ways of turning receiver forgings into complete receivers. Winchester produced M14 receivers automatically, turning forgings into receivers via early NC machines. TRW in particular is notable for their procedure of using high precision forgings which were then cut by enormous chain broaching machines to finished dimensions.

 

Also, the rest of the M14 was production optimized as well. Looking back briefly at the Earle Harvey T25, which had been designed from the ground up to be producible in garages across the United States in the event of nuclear war (no, really), the M14 took a page out of this book as well and was extremely well-suited for distributed production, with almost all other parts besides the barrel, bolt, and receiver able to be cast in the small foundries which were common at the time. In fact, TRW produced only 11 parts for the M14, and outsourced all other parts production to other manufacturers, and were able to offer the M14 to the government at a considerable cost savings as a result ($79.45 per, compared to $95 per for H&R). H&R also subcontracted out most small parts of the rifle.

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5 hours ago, Sturgeon said:

 

Whoah whoah, citation please? They standardized the .280 as the 7mm Mk. 1Z at the same time, so I am not at all convinced that just because the pattern from that batch was adopted as Rifle No. 9 that means they would have been in 7.62mm.

 

Going from the Dugelby book here.

 

"Rifle number 9.  This was the War Office designation of the weapon built after the 1950 trials incorporating all of the suggested modifications.  It was known at Enfield as Rifle number 9 X1-E1.  14 pieces were made and numbered EN-100 to EN-114.  (EN-109 was the piece presented to Mr. Jansen upon his leaving Enfield for Winchester in New Haven, Connecticut, USA, and is now in the Winchester Museum there.)  All are in 7.62mm x 51mm."

 

-pg. 55

 

The parliamentary debates in the UK were indeed over the merits of a .280 EM-2 vs a .300 FAL (they called in ".300" for some reason).  What Parliament seemed to be completely unaware of was the fact that all development of the EM-2 since the 1950 competitive trials had not involved the .280 cartridge at all!  In fact, the only rifles made in a caliber other than 7.62x51mm/T65 were the ten rifles made in Canada in 7mm Compromise.

 

"Even Parliament was kept in the dark as to the state of work and modifications on the EM-2.  Design changes had been carried out as a result of the 1950 trials, and six pieces were newly made by BSA ltd. of Birmingham in the US .300 T65 calibre.  Questions were still being asked in the House in January 1953 in this regard and Mr. Churchill told the house on February, 6 1953 that: "The British, Belgians and Canadians had worked together to provide a round the same length as the American T65, but using the .280 bullet.  (This was the 7mm compromise round) and at the same time he stated that the EM-2 had already been modified to fire both this and the T65 round."  Three examples were ready in the T65 caliber for the 1952 trials, but were withdrawn before the completion of these tests."

 

There is no indication in the record of the Parliamentary debates that the MPs in favor of the EM-2 (and responsible for its "adoption") were aware of the fact that it was no longer chambered in .280 British until Churchill told them so in 1953!

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Nope, @Collimatrix u wrang:

 

Quote
50. Mr. Linstead 

asked the Minister of Defence whether the decision to substitute a.280 automatic rifle for the.303 Short Lee-Enfield has been taken in consultation with the military authorities of the North Atlantic Treaty Organisation and what information he has as to whether this weapon is to be a part of the equipment of the Forces of other European countries which are members of that Organisation.

§Mr. Shinwell 

His Majesty's Government have decided, after extensive trials, to adopt the.280-inch calibre for small arms for the British Forces in substitution for the.303-inch calibre which has been in use for the last 50 years. The adoption of this calibre makes possible the design of a light self-loading rifle which will more than double the maximum rate of a soldier's fire. Before reaching this decision, His Majesty's Government had full consultations with other North Atlantic Treaty Powers. The Standing Group has formally approved the.280-inch rifle as "militarily acceptable," but I have no 379information as to whether any other North Atlantic country has yet decided to follow our example.

 

Mr. Shinwell being the Defense Minister at the time.

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3 minutes ago, mjmoss said:

Welcome to the wonderful world of the EM-2 in which there are many twists and turns along the long road of "wtf did they do that for?"

 

 

I disagree.  The program essentially ran from what, 1949-1953, or thereabouts?  It was a fairly short road of WTF.

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