It’s 200 BHN plate so I guess but the difference between protection and army limit isn’t 6%, it’s much smaller
Still even if we use the reasoning it’s 85-95 or ~90mm
If I remember right the extra plate behind the gun shield is belived to be 25.4 mm (1 inch), and it certainly is that much in WarThunder.
So I suppose a 3.5 inch gun shield would match that, as the documentation I’ve seen on the M26 states a 4.5 inch thickness on the mantlet.
Makes sense, so it would be quoted as 3.5" (LOS) mantlet + 1" perforated internal plate.
Though this isn’t uncommon on other tanks, I assume it isn’t modeled as armor either
What do you think about the Sherman turrets?
There’s not much for me to say. I can only show what the documents I have tell me, and I’m limited in my selection as I simply don’t have access to a lot of documentation (I’m not American).
Every document I’ve ever seen says 3 inch turret front, 2 inch turret rear and sides, but clearly there’s something wrong.
I find US documents make similar errors like for M48, M47 turrets, M48, M60 hull sides, so I went on a little investigation.
It doesn’t seem to bother them if they directly contradicts the factory blueprint (M48)
Honestly I’ve always been interested in seeing more detailed information on the M26’s mantlet.
The blueprint you’ve provided is one I’ve actually seen plenty of times. My problem with it is just that the trunnion mount and all the other details makes it harder to get good measurements on the different thicknesses at different areas.
Right now in game it is around 6 to 5.5 inches thick, not counting the trunnions and gunner sight port, with the additional 1 inch thick plate behind it. I’ve even talked about this exact topic in, well, another topic.
Maybe the mantlet can match it’s real protection level, and not be substantially thicker than its own 3D model, I think that’s a good start.
The mantlet is using variable thickness volumetric armor, therefore the thickness it has is determined by the 3D armor thickness of the plate (that’s why screenshots will say “Armor dimensions at point”, because it is the actual 3D armor model LoS thickness). This can also be seen with the M26’s side armor.
In relation to the actual tank’s 3D model, that’s not really possible to check right now. From the outside the 3D armor model matches the tank’s 3D model, but the inside could just be different.
The 1 inch plate behind the mantlet, for example, is has a 3D armor model that is noticeably thicker than 1 inch. However, since it is not using variable thickness armor this doesn’t matter, the armor thickness it provides is determined by the value that Gaijin puts there.
I literally just noticed that the bottom right of this image shows an inch ruler, so I decided to use it to quickly make measurements of the turret front.
Unless I have seriously done something wrong (maybe the ruler changed scale after I cropped it out and rotated it or something) the blueprint is showing 3 inches on the front, not counting the slight additional thickness that comes from the mounting of the gun shield.
Edit: I decided to do the same but for the other blueprint that shows the entire turret without the gun mount, as it also has a inch ruler on the bottom right. This time I also measured the rear of the turret, and did 2 measurements on each part, for each turret.
Not only does the front continue to show 3 inches, but with this blueprint the rear shows 2 inches.
Live fire testing having a different thickness for the turret rear of 1.75 inches makes sense, since as far as I know cast armor is prone to not matching the especified thickness due to how it is made, at least I remember that being the case.
However these two blueprints seem to just completely disagree with the other one that shows the entire tank. Unfortunately, that one doesn’t have an inch ruler, the only way to get thickness measurements is by pixel comparison, while these two images directly (in a way) state the thickness of the armor.
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The March 1943 blueprint uses 3" thickness, the turrets tested at Cairo showed 2.5" thickness, the transmission cover was 1.75" as was the rear of the turret.
What I think is happening is the presence of multiple subvariants of the turret that aren’t catalogued.
It is surprising that the October 6th 1941 drawing has 3" but some others have thinner. This one is given as D51048A, so it’s a question of what model the tested Sherman turret was.
Or, the mount area itself is thicker for mounting the gun, the turret face itself might not be thicker in early M34 mount turrets.
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I assume that those values come from this document you posted?
From looking at it, it is stating ballistic limits of the different plates of the Sherman against the 6 pounder for different angles. And the last column on the 6 pounder table says “Equiv. thickness”, and with a very well educated guess I’m going to assume that “Equiv.” means equivalent.
So from my understanding, this document is not talking about the actual measured thickness of the plates.
Instead, it is stating the ballistic limits of the plates against the 6 pounder, and comparing those results with documented ballistic limits for the 6 pounder gun, to determine the effectiveness to the plates of the Sherman (or in other words, what the plates perform like). This lines up with why only the 6 pounder has the “Equiv. thickness” column, as the other guns are German guns (88, 75 and 50 mm), which wouldn’t have documented ballistic limits from the British, at least not yet. In fact I wouldn’t be surprised if these results were later used to help determine the ballistic limits for those guns.
This makes sense given that the only plates that are of noticeably lower “equivalent” are those that are cast, which generally is accepted as not being as strong as rolled homogeneous steel. In fact, it is just weaker in game, CHA gets a 0.94 multiplier to it’s thickness for penetration calculations.
Obviously this is all just my understanding from this one single page of the document.
Edit: Nevermind, after looking further I am basically 100% certain of my assesment of this.
It says “I.T.80.D” right under “Equiv. Thickness”. In this case, “I.T.” stands for, if I’m not mistaken, the Izod impact strength test, and the document is specifically comparing the Sherman’s armor plating to an impact strength 80 plate, with D meaning “Deep impression and bulge at back and crack”.
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It’s because it concurs with the armor diagram I posted, one turret is 63.5mm and the transmission cover is thinner. IT.80 and this early Sherman turret cast won’t give that big a difference. The test supports the prints.
The same cast offers ~85% on the front and back, but not the sides? Inconsistently consistent?
Here’s something easier; the transmission cover tapers. And isn’t the same in 1941 and 1943 diagrams.
Diagram for cover
Later cover
Later turret
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I’ll have to get back to you later as today starts the 2nd semester of uni for me so I’m going to be busy until later.
However…
Yeah there’s so many different transmission housings for the Sherman that I can’t even give you a number of how many there are exactly.
IIRC it is sort of like the T-34 where each factory did its own thing for connecting the upper and lower glacis plate, except on top of that the basic design was improved/changed over the course of the war, so each factory did its own thing in different ways as the war progressed.
You can even see a bit of that in the in game models, the M4A1 and Sherman II use a 3 piece completely round transmission housing, a lot of the others use the single piece “sharp” transmission housing and even then there’s different thicknesses between them.
I didn’t know that it tappered even on the early weaker designs though. That’s something that could be bug reported.
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Do you have more of that? Im interested in the Engine deck plate which to my knowlege (and a M4A4 manual) is .1/2 inch or 12,7mm.
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Classes are over for today, finally.
One thing I want to ask is do you know what “I.T.(WTN)” stands for in bottom right of the sketch of the whole M4A2? I couldn’t find anything online after searching. It could just be a coincidence but it could also be related to the British armor plate standards that all start with “I.T.”
That said, onto the armor and all of that.
I disagree with just saying that “IT.80 and this early Sherman turret cast won’t give that big a difference”. You don’t know that, nor do I, unless you’ve done the research and compared results, in which case it’s best to provide evidence rather than just saying “no”. The only thing that document can tell us is that the armor of the Sherman, when compared to an I.T.80 specification plate (which as far as I can tell is a specification for RHA), does not perform like its documented thickness on some areas (it already doesn’t do that in game, due to 0.94 multiplier for cast armor).
I have some hypotheses as to why the turret side armor doesn’t have a lower “equivalent” while the front and rear do, which has mostly to do with the structure and design of the turret.
The front has an obvious hole on it due to the gunshield and gun that go on the middle. The US (temporarily) removed the pistol ports from Sherman turrets because they didn’t like the decreased structural integrity in that specific spot, so it is plausible that the hole on the turret front also leads to such a decrease, therefore worse effectiveness.
The turret of the Sherman, viewed from above, is very much circular. This means that the turret’s side armor curves, and not by little as seen by the image you’ve provided that catalogues the different turrets.
It is possible that the outwards curve provides better structural support from impacts. This is also something that wouldn’t be present on the rear of the turret as it is perfectly flat.
But this mostly just theories and possibilities that I don’t have much way of proving. The only blueprint that shows the different thickness values is the one of the full hull which provides no direct armor values.
Beyond all that, could you tell me how to find these sorts of documents? I’ve been trying for a while but I can’t find anything. I’d love to have a good luck at some Sherman factory drawings in closer detail.
Edit: and what about the M4A2 live fire testing documents? I also couldn’t find them online.
that much angled penetration on a apcbc shell seems unlikely
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that is virtually impossible. the abrams is orders of magnitude more ergonomic and less cramped, not to mention the d25 t is two piece. that is the most inane statements ive ever heard.
i
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exactly this dude is dreaming. like he genuinely think the is2 should load as fast as an abrams despite the Cramped as shit turret, heavier shells, and the 2 part ammo.
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Well, he was talking about the IS-3, which funnily enough has a slightly faster reload than the IS-2 in WT, while the giant bathtub, which is the IS-4M, has the same long reload as the IS-2.
20.8s Ace reload is simply too long to make this vehicle viable at 6.7.
Either the reload buff or drop to 6.3 is needed.
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