I'd buy that....

A hypothetical 40s AR wouldn't have a chrome lined barrel; US small arms didn't get chrome linings until the 50s.

Now we will need to log off and log in on JAR15.com

We will be all known as Jarcommers.

What would have been the point of a cast steel receiver AR-15?

What makes the AR-15 useful and an improvement over previous weapon systems is a combination of design features and technological advancements.

1. 7075 aluminum receiver (not developed until 1943, in Japan of all places)
2. Sub-30 caliber ammunition - the .223 wasn't developed until the early 1960's
3. Modular design - 1913 rails were not developed in 1913.... they were developed in the 1980's
4. Lightweight - dependent upon aluminum receiver set, plastics, and lightweight varmint cartridge

I'm not including things like red dots and ACOGs, or IR lasers, to try to make it somewhat fair.

The bottom line is would an AR-15 variant based on a steel receiver set, wood furniture, no rails, steel mags, and questionable powder / primers / ammo be superior to a M1 Garand or M1/M2 Carbine?

Personally, I'd take the M2.

As complicated as many of the weapons were back then and the massive amount of machining required I'd say easily.

Yes, but not magazines. Magpul didn't exist back then.

I see this more as a question of "Why is the AR-15/M-16 superior to previous small arms" rather than "Could it be done, albeit with different materials and certain sacrifices, earlier in history?"

If it could be done, but it would lack the very attributes that made it better, why would it be worth doing?

The Japanese were making 7075 aluminium aircraft parts in WW2.

Again, the overall design could still be lighter and more shooter-friendly in recoil, plus more resistant to adverse conditions (mud, sand, etc) even if in .30-06 and with the receiver machined from 8620 steel forgings instead of aluminum (US weapons out of castings? Not likely). With .276 Pedersen still in recent memory, you have lighter, relatively small-caliber ammunition. M1913 rails aren't germane because, as you noted, they didn't exist when the real-world AR family was actually designed so that's a red herring. Upper/lower modularity still exists, so there's some room to accommodate future iterations and improvements without having to re-arsenal each weapon.
Heat-shielded Bakelite stocks, pistol grips, and handguards were already possible (indeed, the techniques were already in use for some weapons), and could be made lighter and more weather-resistant than wood. The composite BAR stock is an example, only Ordnance specified it had to weigh the same as the wood version, which meant it was actually quite a bit stronger.

you should read a history book. Sub .30 caliber ammo was in use, and had been since the turn of the century, including a 6mm round being issued to the Navy and Marines in 1895.

Small caliber high velocity ammo had been available since the .250-3000 savage came along in 1915.

As far as the specific aluminum alloy, I'm sure a different readily available alloy would suffice, just like un-heat treated steel, or spot treated steel did in other small arms. Bakelite, the original stock material for the AR was designed in 1907.

Your arguments are not well rooted in the historical record of what was available and when.

ALso...

6061 a popular alloy to make AR's out of had been around since 1935.
https://en.wikipedia.org/wiki/6061_aluminium_alloy#Forgings

@LittlePoney

That is pretty neat looking, thanks for posting!

Parts would have to be redesigned due to metallurgy constraints. I believe 8620 had not been invented yet and thus the bolt and barrel extension would have to be redesigned.

The M16 originally used 6061, which was developed in the 30s.

ETA:  and it worked fine, too, though 7075 was apparently less prone to corrosion issues in the jungles of Nam.

No.

Aluminum problems

Gun powder problems

M1 was made out of machined casting.

Once again.... what makes a steel receiver AR15 better than a M1/M2? 30 carbine isn't exactly hard in terms of recoil. WWII was fought by men that could handle a M1 (or flame thrower).

AR-18 mo better

Oh hell no! We didn't have the advanced technology needed back then for such complicated weapons systems. OP, you're being foolish.

On a completely different subject, I'm a big fan of some of rudimentary and archaic 3,500 horsepower supercharged engines they used during the war. Amazing that any of those planes even got off the ground if you think about it.

No, the M1 was made from FORGED steel. No casting involved. Same with the Carbines and, later, the M14. Ruger's Mini-14 was unconventional because it did use castings, unlike the larger designs from which it's modeled and inspired. (ETA: See here for Springfield Armory National Historic Site photos and article about forging operations, including pictures of M1 receiver production.)
30 Carbine is okay as a pistol replacement or early "PDW" but the biggest problem it has is the lack of reach. A spitzer-bullet, bottlenecked cartridge (like, say, .276 Pedersen aka 7x51mm) is going to have much better external and terminal ballistics.

Nope.

Because Mr. Stoner was only 20 years old and had not yet started his design engineering career.

I want a 30 carbine ar15.

Fuck yeah.

The AR-18 would be a better choice for WWII era manufacturing.  The aluminum forgings for the AR-15 were pretty advanced even by the standards of the late '50s, but stamped steel was standard fare in the '40s.

PMags would've been uglier.

1942 Time capsule...

No 1913 rails? No problem! What would you have hung on them anyway? No practical lasers. Flashlights huge and barely bright enough to give your position away. No logistics for enough batteries. Vertical forward grip? The Army specified straight forends on Thompson SMGs rather than the civilian VFG saying they were too easily broken. Bipod? Who wants to carry that weight?
The forend could be ventilated steel tube, like some other weapons of the day. Pistol grip and stock could be wood or stamped sheetmetal. Possibly the receiver could be stamped sheetmetal?
Our other rifles/SMGs didn’t have chrome bores so that might not be a huge deal.
Given the cult of .30 caliber the cartridge might have resembled the 7.62 X 39 but in ‘merican numbers of course!

No, the AR15 as we know it today couldn't have been mass produced back then.  Could it have been designed back then?  Of course.  Browning is generally credited with using gas from a gunshot (via a hole in the barrel) being used to cycle a firearm circa 1885.  The concept of an intermediate sized cartridge that filled the gap between pistol bullets and rifle bullets goes back to the end of the first world war.  It was dismissed.  The M1 Carbine round was kinda, sorta, but not really in this class of thinking.  David Williams was still thinking in terms of caliber over velocity as were firearms designers of that era.

The AR15 started life as an AR10 firing a 308 Winchester round (some Vietnam vets called this the 30-06 Short).  It ripped off the Browning design of 1885, ripped off Melvin Johnson's bolt head design and added a gas pipe (rather than a forward piston or operating rod system) to actuate the weapon upon firing.  Additionally the AR15 ripped off the STG 44 dust cover and reversed it to come down instead of up.  Direct impingement was already being used in 1940, but not exactly as Stoner/Sullivan used it.  The AR10/15 basically moved the piston system all the way back to the bolt (thus introducing filthy gasses DIRECTLY into the major moving component of the weapon system).

The same reasons that caused the rejection of the AR10 when it was introduced would have caused the rejection of the AR15 in 1942.  It would have had to be made from steel, because aluminum would not have truly been considered.  In those days it was steel and wood, not aluminum.  It would have had to fire the 30-06 round.  Ten pound full auto 30-06 would have suffered from the same disease that full auto 308 AR10's did when tested in the 50s.  The M14 full auto was a failure as a true combat weapons system.  The intermediate cartridge just hadn't come of age yet in 1942.  Even Hitler refused to accept it and his designers were the first to think it up.

So it could have been designed, but its highly unlikely it would have been accepted.  Additionally getting a 22 caliber weapon accepted as a combat rifle would have been laughed out of the building at that time.  It was laughed out of the building when it was introduced later on.  There is still plenty of debate today as to the effectiveness of the 5.56 vs the 7.62mm.  Small arm military combat calibers have shrunk considerably since the late 1870's.  In the American Civil War we generally used 58 caliber Minie balls and now we are shooting 22 caliber high velocity rounds.  People figured out that penetrating a vital organ is what it take to kill or incapacitate an enemy combatant.  War costs money and its far more effective to give a solder 240 rounds of killing power than it is to give a soldier half that capacity of a larger caliber to do the same job.  Firepower counts in a firefight.

Another proof that folks don't think before they ask.  We built thousands of aircraft, hundreds of naval vessels, millions of firearms, artillery pieces et cetera, and had they been invented, you wonder if AR15s/M16s could have been produced in any quantity?

Eta:  Of course we could have.  This is the United States of America, WW2 version.  If we needed it, it would have been delivered.

It looks like 6061 was developed in the mid 1930's, but I don't know how available it was during the war.

Attached File

True.



Aluminum lower "problem" solved:



Yes - they could have done it (or something like it) in 1942.  Just look how quickly Germany went from this:



To this:



But, arguably, Germany had greater "need" for small arms advancements in WW2 (particularly in the Eastern front) than we did.

Our carbines, Garands, and SMGs (along with numbers) fulfilled our needs.

Two people have previously mentioned it, but not in detail.

Yes, not only could a direct impingement rifle be made in 1942, a direct impingement rifle WAS made in 1942.

Specifically, the weapon in question is the Swedish AG-42B Ljungman. Dominion posted a photo of one above. I have one in my safe. I can't say how well it shoots because it is so LONG, (And I mean like, muskets used to form square against cavalry long) that I can bearly get it in my car.

Sweden was neutral, but feared they might be forced into the war. They very rapidly developed a semi automatic battle rifle and issued it more or less as a designated marksman rifle. The AG-42B is by no means an AR-15, it's not even an AR-10, but it is a direct impingement gas system that was fielded during the correct time period.

So yes, the know-how to design something like the AR-15 was certainly around. It might have been made out of steel and used 30-06 with a much larger gastube and be open topped to allow excess powder to escape, but they certainly 'could have' had something like the AR-15, because the Swedish did.

Some of the early prototypes used carbon fiber for the handguard interestingly

Or B-29s...

Came here to post this.  If anyone were to build it the Germans would be the first to do it.  It probably have a stamped sheet steel upper and lower though instead of aluminum
No chrome lined bore.  If I remember there was a problem getting the 223 bore coated at tat time

It is possible. I would guess it would had been steel and wood firearm than a plastic and aluminum combo.

They might have cast the upper receivers in Brass or Bronze, which isn't a huge diversion of war materials (Aluminum was an issue because of aircraft use, bronze and brass was munitions and marine, and we didn't have a shortage of those materials).  They could have made a stamped steel lower like an AR18.  At that point it might have been cheaper then either M1 rifles or carbines...  (think - no need to tie up forging equipment on receivers, less wood used, less steel).  The thing with all the BS on the cartridge development was sort of pathetic, basically they ego stroked themselves into refusing to adopt an existing cartridge, like the 7x57 Mauser, the 300 Savage, or the 250-3000 Savage.

In this thread I learned the Japanese developed 7075.

I did not know that.

I spend a little time around some WW2 aircraft that are still flying and I can tell you that some
of the engine components are very complex.

We would have had no problem building/mass producing an AR15 in the early 1940's.

Doubt anyone would have wanted to forthe reasons already mentioned.

So little actual knowledge being used to make erroneous statements.

Something to think about that contributes to the technology of the M16.

This.

Can we (Arfcom engineers) design a new rifle?

Is that not the engine used on the B50 hence technically a post war engine? It is a work of art though, no mater when it was made.

ETA Pratt & Whitney R-4360 Wasp Major made in 1944

I love engine sectioned views. My university was getting rid of one and I could ahve had it for free, just had no clue how to get moved or stored in my upstairs apartment at the time.

I've got one.  Everybody loves my Johnson.

Melvin Johnson's patented bolt design was used on the AR-15.  He was actually hired by Armalite as a consultant.  

Could it have been made? Yes, most likely, although as said with pressed steel versus aluminum and some other materials substitution.
Would it have been made? Almost certainly not. America was standardized on the 30-06 round for ground combat. We were making billions of rounds per month by 1943 and with that scale of production, the idea that we would convert over to another caliber is ludicrous. As the Italians and Japanese found out, changing such things during wartime is a Very Bad Idea. Could the AR have been made in 30-06? Yes, of course, although again, it would require some serious materials substitution.

Also remember that when the M1 Garand was being tested, a lot of people didn't like it, considering it a "Buck Rogers piece of shit" that was wasteful of ammunition and inaccurate as shit (compared to the M1903). The idea that something like the AR could have been considered, let alone adopted is just silly.

One of the most complicated but still functional guns ever produced is the Remington Model 8, patented in 1900 and first produced in 1905.

Yeah an AR would have been easy... However, cost would have been high due to materials and production methods. Also, as stated, it needs more modern and cleaner powder for high use between cleanings.

They can be built with aluminum other than 7075.  While it is probably the best choice, there are other viable options.

I've asked it many times - what is a m2 carbine with select fire in 5.7 spitfire, 30rd magazine and a folding stock?

Now THAT would have been a gun!

Just make the receiver out of 6061.  That's been pretty much every budget AR ever and it seems to work well enough.

Pretty nice, but you know what this really needs  to make it perfect?

More cylinders