USA: Early M4 hulls with L40 gun?

[Copernicus]

There does not seem to be any unit to cover the early M4 (welded hull) equipped with the L40 gun. As far as I can tell, all early M4's seem to be equipped with the L37 gun. The only M4 variants in game available in 1942 with the L40 gun seem to be the M4A1's, with the cast hull.

Is this intentional?

[Mobhack]

The penetration of both guns are the same, with the only real difference being one point in accuracy, so the things are basically identical.

I vaguely recall a massive data check on the varicose Sherman variants being done a decade or so back in the MSDOS days. Up until then, I had just thought that a 75mm Sherman was just a 75mm Sherman..

Since nobody has brought this point up since then, if it is a valid point, then I suppose that everyone is happy with the existing Sherman models?

(Me, I just find the one with the best frontal armour as a general rule and buy that).

[Copernicus]

Originally Posted by Mobhack

The penetration of both guns are the same, with the only real difference being one point in accuracy, so the things are basically identical.

Want that extra point of accuracy dangit! Heh.

Looks like The M4A3E2 (76) #022 and #186 are duplicates, so maybe one of those can become the M4 L40?

[DRG]

Originally Posted by Copernicus

.

Looks like The M4A3E2 (76) #022 and #186 are duplicates,

Yes, they are,.......... will investigate.................

edit.........

HA!.......it's been that way for over 12 years and if anyone noticed before this they kept it to themselves

[Mobhack]

So which M4(mouthful) do you actually want then, what start date, and as I would not know a "cast hull" from a "welded hull" if it bit me, what armour scheme?. Is it just a copy and paste of an existing M4(mumble) with a new gun and name? - if so, just say "Copy unit #xx, give it the L40 gun and the jumble of letters and digits becomes M4Abc123"...

(I can see why we Brits renamed US things with real names in WW2, not some M-number and a jumble of letters and digits.. Which M3, did sir mean - the light tank M3, half track M3, the medium tank M3, the M3 SMG, the Tractor Crane (2 ton) M3. Much easier to use proper names for things! )

[Copernicus]

Originally Posted by Mobhack

So which M4(mouthful) do you actually want then, what start date, and as I would not know a "cast hull" from a "welded hull" if it bit me, what armour scheme?.

Well... the idea was to copy unit #302/303 to give them the L40 (Weapon 47).

But...

Now that I'm looking into this some more, I'm kind of doubting whether there actually was a distinct L37 version of the M4's gun at all. The only reference I can find that mentions both the L37 and L/40 is in wikipedia:

https://en.wikipedia.org/wiki/75_mm_Gun_M2/M3/M6

Which says: "Barrel length: 40(37.5) calibres (3 m)". The same page also refers to it as the "75mm/L40." I can't find any document that actually refers to the 75mm/L40 and 75mm/L37 (or 37.5) as distinct weapons. One might refer to the "75mm M3" (gun, not tank) as either the L37 or L40, but never refer to each as distinct weapons.

It looks like it might just be that some documents rounded up. In which case, the fix would be to replace all weapon #45's with weapon #47.

But I would like for someone who knows Shermans better than I to confirm...

[Cross]

Originally Posted by Copernicus

Well... the idea was to copy unit #302/303 to give them the L40 (Weapon 47).

But...

Now that I'm looking into this some more, I'm kind of doubting whether there actually was a distinct L37 version of the M4's gun at all. The only reference I can find that mentions both the L37 and L/40 is in wikipedia:

https://en.wikipedia.org/wiki/75_mm_Gun_M2/M3/M6

Which says: "Barrel length: 40(37.5) calibres (3 m)". The same page also refers to it as the "75mm/L40." I can't find any document that actually refers to the 75mm/L40 and 75mm/L37 (or 37.5) as distinct weapons. One might refer to the "75mm M3" (gun, not tank) as either the L37 or L40, but never refer to each as distinct weapons.

It looks like it might just be that some documents rounded up. In which case, the fix would be to replace all weapon #45's with weapon #47.

But I would like for someone who knows Shermans better than I to confirm...

I'm no expert, but I can tell you that British and US barrel lengths were measured from the mouth of the chamber to the barrel end (bore length), but continental nations, including the USSR, measured from the rear face of the breech, giving a longer measured length.

Therefore, the British and US would call it a L40, but if the Soviets bothered to do their own measurements they'd call it a L46, or there abouts.

Because of this, US and Brit guns get the 'short end of the stick' in almost all games that use barrel length calculations.


As for hulls.

I think there were 6 hull types:

• Early Cast dry tiny hatches
• Late Cast wet large hatches
• Early Welded dry small hatches
• Late Welded wet large hatches
• Composite welded
• HVSS Wider with wider tracks

3 nose types:

• Three piece bolted flanges
• Soft nose casting - rolls under smoothly
• Sharp wedge shaped front

3 Turret Types:

• Single hatch early short 75mm One hatch 2 lids
• Two hatch later 75 or 105mm 1 large 1 small hatch
• T23 last long 76mm 2 hatches large

British to US conversion:

• Sherman I = M4
• Sherman II = M4A1
• Sherman III = M4A2
• Sherman IV = M4A3
• Sherman V = M4A4
• Sherman IIAY + HVSS

Gun types/naming conventions:

No notation = 75mm
A = 76mm
B = 105mm
C = 17pdr
and so on so an Sherman IIIC was a M4A2 w/ 17 pound gun.

W = wet storage
E8 = (76)W HVSS
Jumbo = Thicker armour




Cross

[Copernicus]

Originally Posted by Cross

As for hulls.

I think there were 6 hull types:

• Early Cast dry tiny hatches
• Late Cast wet large hatches
• Early Welded dry small hatches
• Late Welded wet large hatches
• Composite welded
• HVSS Wider with wider tracks

There were some welded (M4A2) and cast (M4A1) hulls with dry stowage and large hatches (in the M4A2's), if these sources are accurate:

"Starting in late 1943, the 56° glacis on the M4A2 was replaced by a single-piece plate inclined at 47° from vertical. The 56° glacis featured protruding drivers' hoods with direct vision slots on early tanks and periscopes on later vehicles, and the glacis plate was composed of several pieces welded together, which complicated production. The 47° plate was a single piece and eliminated the drivers' hoods. Larger drivers' hatches were also introduced with the 47° plate. 75mm gun M4A2s were produced with dry stowage and the 47° glacis until replaced on the factory line in May 1944 by wet stowage 76mm gun tanks."

"In late 1943, M4A1 hulls were changed to incorporate larger drivers' hatches and a thicker 2.5" (6.4cm) glacis inclined at 47° instead of 56°. About 100 M4A1s were built with the 47° glacis and dry stowage, and all of these were armed with the 75mm gun M3. Unlike earlier dry stowage tanks, the castings themselves on these vehicles were thickened over the vulnerable areas."

http://afvdb.50megs.com/usa/m4sherman.html#M4A2

---

"Our Archival research has not as yet uncovered any documentation that states exactly when the large hatch, welded hull Sherman entered production, but it is thought that the M4A2(75) shown above may have been one of the first. This tank was evaluated at General Motors Proving Ground and is stated to have been Serial Number 27283 / USA 3035813 indicating November 1943 acceptance. The large hatch M4A2(75) was slated for termination, and did NOT incorporate one of the features of the "ultimate Sherman" - Wet Stowage. Consequently appliqué armor was factory installed on the sides of the hull to protect the ammo bins which remained mounted on the sponsons as on the original Sherman design."

http://the.shadock.free.fr/sherman_m...gehatches.html

Granted, that's not very many. And the M4A2's were mostly (exclusively?) USMC. And the 105mm armed versions had a stowage that was not wet, but offered other modifications that achieved the same effect, if I'm understanding it correctly.

---

All of this looks to be pretty well represented in the game, by the way. Large hatches improved crew survivability by allowing for better escapes, I assume. And wet stowage greatly decreased ammunition fires (although it had little to do with wetness). From what I can tell:

Survivability 2 = Dry stowage small hatch.
Survivability 3 = Dry stowage large hatch.
Survivability 4 = Wet stowage large hatch.

Additionally, the frontal armor values:

Cast small hatch: 51mm @ 55 deg.
Cast large hatch: 64mm @ 47 deg.

Welded small hatch: 51mm @ 56 deg.
Welded large hatch: 64mm @ 47 deg.

I'm led to believe that the cast hulls offered less protection than the welded ones for the same armor values, though.

(All HVSS hulls had the large hatches, I think, except for a few post-war modified tanks. I'm not sure where the composites fit into this.)

[Griefbringer]

Originally Posted by Mobhack

(I can see why we Brits renamed US things with real names in WW2, not some M-number and a jumble of letters and digits.. Which M3, did sir mean - the light tank M3, half track M3, the medium tank M3, the M3 SMG, the Tractor Crane (2 ton) M3. Much easier to use proper names for things! )

Don't forget the M3 howitzer (not to be confused with M3 gun).

[Copernicus]

Originally Posted by Griefbringer

Don't forget the M3 howitzer (not to be confused with M3 gun).

Heh. Yeah, it's pretty crazy.

"Is there some reason a robot made of wax can't take a nap standing up in the middle of a bunch of wax robots? Or does that confuse you?"

https://www.youtube.com/watch?v=MkJDuLbR170