Rearm the American Infantry for WWII.

[Deleted member 1487]

the development of the t2 cartridge mirrors what happened to the .280 brit in the 50's
the rim diameter went from 11.4mm to 12.0 mm
this suggests the intent of moving away from the dimensions of the original .276

Since the rest was covered by others, the issue with the case expansion was twofold: first they needed the larger case to allow for the use of existing service powders to get the same performance if needed (aka there was any issue with the expansion of the supply of the new powder Pedersen used) which AFAIK were lower energy so required more grains of powder to achieve the same pressure. Second there was no need for the heavily tapered case of the .276 Pedersen 'original' because they didn't need to extract it from the Pedersen delayed blowback rifle, which did not use flutes to aid extraction (delayed blowback extracts at higher pressures than gas piston systems due to cycling more quickly) but rather a high degree of taper and lubricated cartridges (hard wax that only melted at over 200 degrees F). So without any need for the Pedersen case dimensions and to allow for use of older existing production powders the 12mm diameter case was basically the only option the army would accept. Plus the added bonus of not having to use a different set of machines to make the cartridge case, which cut down on tooling expenses. Given the budget issues after 1929 that makes all the sense in the world.

The situation with the British cartridge is a bit different, but many of the same elements are still there. Stupidly, despite testing the CETME ammo and rifle at the same time as they were developing the M14 and 7.62 NATO, they didn't take any hints from Spanish/German bullet designs which fixed the problem (could still use 7.62 and shortened .30-06 cases!) and would have worked in the rifle designs everyone wanted.

 

[Capt Thunderbolt]

So without any need for the Pedersen case dimensions and to allow for use of older existing production powders the 12mm diameter case was basically the only option the army would accept. Plus the added bonus of not having to use a different set of machines to make the cartridge case, which cut down on tooling expenses. Given the budget issues after 1929 that makes all the sense in the world.

One thing I could never understand with M1 and .30-06”, it only fitted 8 rounds. The clip is only ~1.6mm wider and ~3.0mm deeper, but nearly 10mm longer. Why didn’t “just” adopt it.

The T3 Garand “ammo well” is much deeper, than the M1. See video

Nat’ raises that the Pedersen is NOT lower pressure. But Ian, in the T3E2 video notes the much lower profile breach and barrel, and the straight operating rod (unlike M1).



Barnes cartridges notes that most of the Pedersen trails round were Carcano rounds, necked out to 7mm. The 6.5 Carcano is almost identical to Pedersen and runs at a pressure of 41k (~2/3 of .30-06!)

To only produce 2,500 T2 seems way too low for developing rounds. It suggests that it was only for deep seated AP and tracer? The internal ballistics were well known?

Put all the above together, I suggest this hypothesis......????

The thicker heavier barrel, prevents the operating rod, activating the round elevating plate, rising as designed? The taper of the Pedersen, allowed the fulcrum work effectively? The longer heavier .30-06 messed it up due to longer activation arm.

Had the T2 ammo been adopted, the barrel profile would be the same as T3 Garand, and only 3mm deeper in well.

Would a .276” T2 ammo Garand really only have 8 rounds.......?

 

[Cryhavoc101]

i don't understand why you quoted that particular post,
but ok,
my current understanding is that the V-P rifle was chambered for the t1 cartridge
that the V-P was never chambered for the t2 cartridge
and that the garand that was chambered for the t1 cartridge used a 10 rnd clip similar to the V-P's 10 rnd clip
if you're referring to a theoretical garand rifle using the t2 cartridge that @wiking is pushing (i'll refer to this as the t4 from now on) that would run into the same issues as the otl .30 cal garand, and a choice between keep the same capacity and lengthening the mag or keep the mag the same length and reducing capacity

I was responding (admittedly somewhat lazily) to the general conversation not too any individual

I think one of the issues with the .276 is that it pretty much gets to where it is wanted to be as a rifle round and then has additional requirements 'inflicted' upon it - such as also having to act as a suitable machine gun round which quite frankly was too much creep to the original intention of the design and proved to be too much especially in the conservative mind set of the military.

Better to have kept the .276 (T1?) as the rifle and LMG round and retained (and possibly improved?) the 30-06 as the MMG round for the M1919s which would not be a logistical issue as the MMG ammo was supplied 'at the point of use' (Company and above?) in belts in boxes (I understand this to be a 250 round cloth belt?) while the Rifle and LMG ammo would be supplied again 'at the point of use' in Bandioliers of 6 x 10 round Enbloc clips with the .276 ZB26 clone LMG magazines reloaded using this ammo at the Squad level.

 

[stephen the barbarian]

Snip

right, they changed the case to improve the performance and lower the cost
i understand that

I think one of the issues with the .276 is that it pretty much gets to where it is wanted to be as a rifle round and then has additional requirements 'inflicted' upon it

yes, and no,
i think the major issue in this debate stems from many of the proponents of the .276 are thinking of it as an ideal rifle cartridge in a semi auto battle rifle and the .30-06 as a compromise
my general interpretation is that ordinance att thought of .30-06 as the ideal, with .276 as the compromise
iow, it did what pederson claimed it would do, but not what ordinance wanted

 

[Deleted member 1487]

my general interpretation is that ordinance att thought of .30-06 as the ideal, with .276 as the compromise

Not sure why you'd think that, given that both were specialized cartridges, optimized to do specific things. .276 Pedersen was designed around military requests, thing is their requests changed later in response to budget issues stemming from the Depression. It went from being only a rifle cartridge to being a .30-06 replacement in all roles, and ultimately once the military decided, for budget reasons, to stick to the existing cartridge for their universal one it was game over.

 

[jeandebueil]

IMHO, all this debate about the cartridges, while being interesting and even stimulating, maybe prevents us to focus on which simple and easy to implement actions we could choose to have a well-equipped US Infantry.

Thing is, the US Infantry from OTL IS well-equipped and only minor changes would turn it to a very well-equipped one.
-30-06 for WW2 is a good enough cartridge and in use for already 40 years. Let's just keep it.

-M1 Garand, OTL simplified Thompson SMG, 1919 MGs and M2 HMGs are good weapons. Same thing for the M1903/M1917 as sniper rifles and 60 mm/81mm mortars. Keep them and use them as OTL.

-Bazookas is a good design (so good the Germans copied it) but anti-tank guns are the real tank killers. Keep the 57mm AT gun and just introduce a towed version of the 76mm one. Again, nothing fancy or complicated, but effective.

-Maybe simplify the Colt 1911 just a bit: no need for a grip safety for instance and it saves a couple of cents per gun. Not much but still welcome.

-The M1 carbine is indeed a good design and was popular for a reason. But it adds yet another kind of cartridge. War production and Logistics Corps don't need that. Instead, ramp up Grease gun's production, using this time the same, reliable magazine as the Thompson. Again, ease logistics and war production. Cheap, reliable, controllable SMG, perfect for tank and heavy weapons' crews.

-REPLACE THE BAR. Seriously, that's the only thing which really needs to be done. If you want a weapon relatively similar, take the French FM24/29 (itself taking meany features from the BAR) and the US is already taking inspiration from French designs (see their mortars) so why not an LMG. Of course, the best idea would be to actually adopt the RUGER prototype. But perhaps the quartermasters will be against such an innovative design. So the FM 24/29, similar to something they know (plus it's French and the US Army was really pro-French for their doctrine before 1940) will be adequate.

See? FIVE relatively small changes (except for the last one). It is what it takes to give US Infantry an excellent arsenal. Shows that they were on the right path OTL. And you can do it by keeping things simple and cheap. Even cheaper than OTL.

 

[Cryhavoc101]

-The M1 carbine is indeed a good design and was popular for a reason. But it adds yet another kind of cartridge. War production and Logistics Corps don't need that. Instead, ramp up Grease gun's production, using this time the same, reliable magazine as the Thompson. Again, ease logistics and war production. Cheap, reliable, controllable SMG, perfect for tank and heavy weapons' crews.

I would argue the reverse is true

M1 Carbine >SMG

Its lighter and the bullets are more effective at longer ranges than .45 and have much greater energy with perhaps the 45 having an advantage only at very close range

Bullet mass/type	Velocity	Energy
110 gr (7 g) FMJ (.30 carbine)	1,990 ft/s (610 m/s)	967 ft⋅lbf (1,311 J)

230 gr (15 g) FMJ, Winchester (.45)

835 ft/s (255 m/s)

356 ft⋅lbf (483 J)

Make the M1 select fire from the beginning as the original guns were intended to be - provide it with a 30 round Banana mag earlier

No need for M3 or continued production of Thompson at all - and remove the .45 from the logistics chain (except for the handful you would need for those still packing a 1911)!

But at the end of the day small arms ammo is a tiny % of a infantry units logistical slice so having both .45 and .30 carbine in the logistics train is not going to cause any appreciable issues and was done OTL anyway with no difficulty as far as I am aware.

So why not have both?

 

[Peg Leg Pom]

The .280 is totally different.
GB had what they wanted, adapted the rifle to go with it, and then bent over backwards to please the US. It wouldn’t have mattered if they produced a laser blaster, if it wasn’t .30”, it was not going to be acceptable to the US!

Blasters have terrible accuracy, a lousy rate of fire and are short ranged so of course they'd be rejected.

 

[Crowbar Six]

IMHO, all this debate about the cartridges, while being interesting and even stimulating, maybe prevents us to focus on which simple and easy to implement actions we could choose to have a well-equipped US Infantry.

Thing is, the US Infantry from OTL IS well-equipped and only minor changes would turn it to a very well-equipped one.
-30-06 for WW2 is a good enough cartridge and in use for already 40 years. Let's just keep it.

-M1 Garand, OTL simplified Thompson SMG, 1919 MGs and M2 HMGs are good weapons. Same thing for the M1903/M1917 as sniper rifles and 60 mm/81mm mortars. Keep them and use them as OTL.

-Bazookas is a good design (so good the Germans copied it) but anti-tank guns are the real tank killers. Keep the 57mm AT gun and just introduce a towed version of the 76mm one. Again, nothing fancy or complicated, but effective.

-Maybe simplify the Colt 1911 just a bit: no need for a grip safety for instance and it saves a couple of cents per gun. Not much but still welcome.

-The M1 carbine is indeed a good design and was popular for a reason. But it adds yet another kind of cartridge. War production and Logistics Corps don't need that. Instead, ramp up Grease gun's production, using this time the same, reliable magazine as the Thompson. Again, ease logistics and war production. Cheap, reliable, controllable SMG, perfect for tank and heavy weapons' crews.

-REPLACE THE BAR. Seriously, that's the only thing which really needs to be done. If you want a weapon relatively similar, take the French FM24/29 (itself taking meany features from the BAR) and the US is already taking inspiration from French designs (see their mortars) so why not an LMG. Of course, the best idea would be to actually adopt the RUGER prototype. But perhaps the quartermasters will be against such an innovative design. So the FM 24/29, similar to something they know (plus it's French and the US Army was really pro-French for their doctrine before 1940) will be adequate.

See? FIVE relatively small changes (except for the last one). It is what it takes to give US Infantry an excellent arsenal. Shows that they were on the right path OTL. And you can do it by keeping things simple and cheap. Even cheaper than OTL.

The problem was in the 1930's the USA only had one SMG available which was the Thompson M1928, there were only limited stocks as Thompson had 15000 made by Colt in 1921 and they didn't even have production facilities so there was no in production alternative. SMG's were considered short ranged and inaccurate by the US Army, the M1 carbine was a lot more accurate than a Thompson and way cheaper to make, I also suspect they didn't trust a clerk or truck driver with a fully automatic weapon, at least in 1940, no doubt opinions changed later in the war.

To get a SMG in production they would need to start in 1938 (peacetime constraints) and get the Ordinance Dept to not build something with wooden furniture, lots of machining and well finished... good luck with that. In 1941 they had other things on their minds and so they went M1 Thompson, M2 (went nowhere) and M3 Grease Gun.

 

[jeandebueil]

The problem was in the 1930's the USA only had one SMG available which was the Thompson M1928, there were only limited stocks as Thompson had 15000 made by Colt in 1921 and they didn't even have production facilities so there was no in production alternative. SMG's were considered short ranged and inaccurate by the US Army, the M1 carbine was a lot more accurate than a Thompson and way cheaper to make, I also suspect they didn't trust a clerk or truck driver with a fully automatic weapon, at least in 1940, no doubt opinions changed later in the war.

To get a SMG in production they would need to start in 1938 (peacetime constraints) and get the Ordinance Dept to not build something with wooden furniture, lots of machining and well finished... good luck with that. In 1941 they had other things on their minds and so they went M1 Thompson, M2 (went nowhere) and M3 Grease Gun.

The problem with the M1 carbine is while it's a good carbine, it is not as good when used as a beefed up SMG: recoil is much more important and thus accuracy suffers. Honestly, a cheap SMG (3 times cheaper than a carbine) which is easy to use and very controllable is better. At less than 100 metres, a M3 Grease Gun firing bursts of 45 ACP with good stopping power is perfectly adequate for heavy weapons' crews being forced to defend themselves.

 

[Deleted member 1487]

The problem with the M1 carbine is while it's a good carbine, it is not as good when used as a beefed up SMG: recoil is much more important and thus accuracy suffers. Honestly, a cheap SMG (3 times cheaper than a carbine) which is easy to use and very controllable is better. At less than 100 metres, a M3 Grease Gun firing bursts of 45 ACP with good stopping power is perfectly adequate for heavy weapons' crews being forced to defend themselves.

From what I've read it's more like 50m for the M3 grease gun.
The M2 would have been very controllable in .22 and much more lethal.

 

[Crowbar Six]

The problem with the M1 carbine is while it's a good carbine, it is not as good when used as a beefed up SMG: recoil is much more important and thus accuracy suffers. Honestly, a cheap SMG (3 times cheaper than a carbine) which is easy to use and very controllable is better. At less than 100 metres, a M3 Grease Gun firing bursts of 45 ACP with good stopping power is perfectly adequate for heavy weapons' crews being forced to defend themselves.

That isn't how things looked to Ordinance. You would need a time machine and a baseball bat to persuade them they were wrong and they would still get it wrong 9 times out of 10.

 

[jeandebueil]

From what I've read it's more like 50m for the M3 grease gun.
The M2 would have been very controllable in .22 and much more lethal.

The M3 is a like a Sten but better. A Sten had an effective combat range of 80 metres. So, it's safe to assume that the M3 can achieve the same level of relative accuracy.
And while I agree with you on the idea that the .22 is a better cartridge, we must keep in mind that the Army would more likely use ammo it's familiar with. 30-06 and 45 ACP have been in service for 30 years and provided ample satisfaction (at least according to the persons in charge).
If you want to be effective, you must keep it simple and rationalize everything as much as possible. This means doing the best you can with designs already existing instead of introducing new designs which might cost you time and money, even if they're better.
And an M3, against Japanese Infantry, is more than adequate (and dirt cheap compared to the M1 or M2 carbine). You're loading a mortar, someone runs towards you. Take your M3, use your finger to arm the thing, point and fire a burst, while your buddies do the same. You're creating a wall of bullets which protect you with a weapon easy to produce, easy to use and requiring very little training. That's perfect for a war economy and soldiers who must spend little time training with small arms and a lot of time with heavy weapons.

The M2 is an excellent weapon for an Army which isn't as massive as the US Army of WW2. For the 1941-1945, you need guns, a lot of them, while reducing the costs and simplifying the logistics as much as possible. Do not add a fourth cartridge to the three the Infantry is already using.
Simplicity is the mother of all victories.

 

[Cryhavoc101]

Blasters have terrible accuracy, a lousy rate of fire and are short ranged so of course they'd be rejected.

What? Rubbish!!!!

 

[marathag]

just introduce a towed version of the 76mm one. Again, nothing fancy or complicated, but effective

There was a model championed by Devers in 1943, but was spiked by McNair, who was a fan of the 3" he had a hand in developing.
But for AT gun use on the ground, speeding the development of the lightweight 75mm, as used on the B-25 medium bomber, and use that on the 57mm carriage. The recoil energy is similar between the two, and a muzzle brake can be added.
Unless the T45 APCR round is Standardized, it won't be as good a hole puncher as the 57mm, but will have the whole host of 75mm ammo to choose from, like HE and WP Smoke.
This could have been ready for the Italian campaign, and it woukd be a good thing to replace the 37mm, that was still around with the 5thArmy thru 1944.

 

[marathag]

The problem with the M1 carbine is while it's a good carbine, it is not as good when used as a beefed up SMG: recoil is much more important and thus accuracy suffers.

The M2 Carbine on FA has similar recoil to the M16A1 on FA.
It's not a problem.

 

[Deleted member 1487]

The M3 is a like a Sten but better. A Sten had an effective combat range of 80 metres. So, it's safe to assume that the M3 can achieve the same level of relative accuracy.

Agree to disagree on that. The M3 had a lower powdered cartridge and a shorter barrel. The Sten most certainly had a longer effective range than the M3 and better accuracy.

And while I agree with you on the idea that the .22 is a better cartridge, we must keep in mind that the Army would more likely use ammo it's familiar with. 30-06 and 45 ACP have been in service for 30 years and provided ample satisfaction (at least according to the persons in charge).

Yet the .30 carbine was a thing and one of the most mass produced cartridges of the war given that the M1 carbine was produced in greater numbers than the Garand.
And the .22 cartridge would simply be a necked .30 carbine as the .22 spitfire:

.22 Spitfire - Wikipedia

en.wikipedia.org

Literally the only difference to the Carbine would be a different barrel.

If you want to be effective, you must keep it simple and rationalize everything as much as possible. This means doing the best you can with designs already existing instead of introducing new designs which might cost you time and money, even if they're better.

This is the US we're talking about, they spent more money on small arms than the Manhattan project and helped equip the Soviets, British, Chinese, and many more. They didn't GAF about simplicity and rationalization because of how enormous the industrial output of the economy was.

And an M3, against Japanese Infantry, is more than adequate (and dirt cheap compared to the M1 or M2 carbine). You're loading a mortar, someone runs towards you. Take your M3, use your finger to arm the thing, point and fire a burst, while your buddies do the same. You're creating a wall of bullets which protect you with a weapon easy to produce, easy to use and requiring very little training. That's perfect for a war economy and soldiers who must spend litte time training with small arms and a lot of time with heavy weapons.

As a PDW within 50m sure. However if you look at Marine TOE the carbines were favored due to their much greater stopping power and range if needed. If it were so obvious the US infantry in the field would have done what you say, but they didn't, they wanted the carbine.

The M2 is an excellent weapon for an Army which isn't as massive as the US Army of WW2. For the 1941-1945, you need guns, a lot of them, while reducing the costs and simplifying the logistics as much as possible. Do not add a fourth cartridge to the three the Infantry is already using.

I don't think you really realize just how many carbines were produced during and after WW2. It well exceeded the M3 SMG by a huge margin; it was quite cheap, very easy to use, highly preferred in many cases to any other weapon (even the friggin' Germans used it when they could get one, the only US weapon they took if they had a choice).
Reducing cost and simplifying were simply not needed given the US economy and it is beyond silly to even suggest that they were under the constraints anyone else was. If the Germans could get by with their mess of firearms and ammo types the US could and did breeze through with a somewhat less bad mess of small arms.

Simplicity is the mother of all victories.

Shockingly the US still one despite not having simplicity. They had industrial might, which conquers all.

 

[Peg Leg Pom]

Shockingly the US still one despite not having simplicity. They had industrial might, which conquers all.

Quantity has a quality all of it's own.

 

[Deleted member 1487]

Quantity has a quality all of it's own.

Quality and quantity beats all, which is the US system.

 

[Cryhavoc101]

The problem with the M1 carbine is while it's a good carbine, it is not as good when used as a beefed up SMG: recoil is much more important and thus accuracy suffers. Honestly, a cheap SMG (3 times cheaper than a carbine) which is easy to use and very controllable is better. At less than 100 metres, a M3 Grease Gun firing bursts of 45 ACP with good stopping power is perfectly adequate for heavy weapons' crews being forced to defend themselves.

Yeah - but the Carbine would be better and lighter and for all the other jobs your Radioman, runner, mortar man, MMG team member, driver might be pushed into doing it would be a better gun than the M3.

And so it proved with the M3 pretty much retained as a tankers weapon with the M1/M2 used for pretty much everything else

It was more expensive than the M3 for sure - but also cheaper than an M1 Garand and given the huge numbers of Carbines built and the massive amount of ammunition and magazines produced it was not an issue.

Edit: I would also add that of the principle US Weapons (Thompson, Grease gun, Garand and Carbine) the Germans liked the Carbine the most for the same reason why I place it as the best small arm of WW2 - it was light handy, well made and effective at most ranges that battles took place at.

EDIT 2: Just saw that Viking said the same thing!