Summary of the Russian 76mm against 80mm StuGs?

[Redwolf]

Lorrin, Jason, troops,

does anybody have pointers to threads ready where you guys where evaluating whether the 76mm gun could defeat 80mm StuGs in reality?

I apologize for the lame request but the search interface works very badly for a request like that where the search terms aren't just words, but technical terms with units.

Thanks.

[lorrin]

Originally posted by Redwolf:

Lorrin, Jason, troops,

does anybody have pointers to threads ready where you guys where evaluating whether the 76mm gun could defeat 80mm StuGs in reality?

I apologize for the lame request but the search interface works very badly for a request like that where the search terms aren't just words, but technical terms with units.

Thanks.

Sorry, but I don't keep them. JasonC and a few of the other regular contributors to the various discussions are the best bet.

Lorrin

[MikeyD]

I recall some of the discussion on this topic. Opinion was that the Stug had been uparmored to meet that specific T34 gun threat so its no surprise that 80mm achieves that goal. Still, the Stug isn't a clean design. For instance there's the driver's visor and that small near-vertical plate at the top of the hull, and who khows what would happen if you could skate a big HE round into the gap between the pig's-head mantlet and the hull.

I can't give numbers, just observations.

[Mr. Tittles]

The StuG is a self propelled gun in that the gun is actually mounted to the floor of the chassis like a naval weapon is mounted to a ship deck. That armored box mantlet or even the pigs head mantlet does not cradle the weapon.

The Hetzer of Jagdpanzer IV or Jagdpanther give a much better armor envelope. The gun is actually mounted to the front armor.

A gun hit on the mantlet of a StuG would actually throw the weapons zero off even if it did not penetrate.

The use of tracks as armor and its protection level is not very well understood. The Germans certainly used concrete and tracks (even T34 tracks) as protection. They must have felt it was worth it and I would be surprised if it did not offer some protection. The very steeply sloped upper armor may have offered good skip protection. I have not seen any pics of this armor penetrated.

[lorrin]

The past discussions centered on the following pro and con issues (StuG IIIG and PzKpfw IV generally carry face-hardened armor on front):

A. British firing tests against 32mm/30mm layered (in contact) face-hardened armor on PzKpfw IIIH front with 37mm thru 75mm AP and APCBC results in an effective single plate resistance of 69mm for the two plates.

B. American tests with 37mm thru 90mm APCBC against 30mm/50mm layered (in contact) face-hardened armor on front of PzKpfw IV shows that best test resistance is much greater than a single 80mm plate would provide

C. Standard 76mm APBC from T34 would penetrate about 82mm face-hardened at 100m and 75mm at 500m.

Since StuG IIIG and PzKpfw IVH carried single plate thicknesses of 80mm face-hardened or layered armor with resistance above 80mm, penetrations at 500m should be rare

D. Russians had super hardened, limited availability 76mm APBC round for T34 and field guns that penetrated 90mm face-hardened at 100m and 82mm at 500m, which matches 500m penetration range quoted by JasonC

E. Russians also had solid shot uncapped AP designed to kill Tigers from side, which penetrated about 74mm face-hardened at 500m

F. Upper superstructure armor on StuG IIIG is highly sloped but thin, 50mm at 51 degrees from vertical and 30mm at 68 degrees from vertical, where the thinner plates which might be vulnerable to 76mm APBC at 500m despite large impact angles (APBC is very good against sloped armor due to flat nose, which cancels many of the ricochet forces that plague sharp or rounded nose ammo).

G. Near vertical 30mm/50mm armor on front of StuG IIIG has large bolts and openings through it, is made up of limited size plate and probably would suffer from edge effects on many hits(lowered resistance when hits land near free ends), making it vulnerable to T34 76.2 APBC.

H. Tests and combat results from various sources confirm that 2 pdr AP was not very effective against 32mm/30mm on PzKpfw IIIH front

I. Combat results with 25 pdr AP against PzKpfw IIIH front suggest resistance equal to 62mm face-hardened and maybe more

J. Two homogeneous plates in contact resist penetration with less than the total thickness, because homogeneous armor has less resistance at the surface and there are four surfaces with two plates in contact versus two with one plate.

Two face-hardened armor plates in contact present two separate face-hardened layers which have a total combined thickness greater than a single plate with same overall thickness, first face-hardened layer removes armor piercing cap or blunts uncapped AP reducing effectiveness against second face-hardened layer

K. Germans gave up on 32mm/30mm face-hardened on front of PzKpfw IIIH and went with single 50mm plates on PzKpfw IIIJ, suggesting 32mm/30mm about the same as one 50mm plate. Germans switch from 32mm/30mm because two bolted plates in contact became a maintenance headache, angled hits tended to shear or bend bolts loosening connections

[Mr. Tittles]

I challenge anyone to find a pic of a StuG III's steeply sloped upper armor being penetrated. I have never seen one.

Steeply sloped armor is very hard to penetrate.

[Redwolf]

Thanks so much, lorrin.

BTW, do you plan to publish an updated version of your booklet?

[YankeeDog]

Didn't someone make an argument that the armor on StuG's gun mantlet was thin enough to be penetrated by the 76mm, and also that the mantlet is actually a relatively good-sized target on the Stug?

Going by foggy memory here. . .

Cheers,

YD

[MikeyD]

There's the early and quite vulnerable flat plate mantlet, followed by that sculpted cast 'pig's-head' mantlet (though I understand the Germans never actually referred to it as such during the war). For a weapon system supposedly invulnerable to attack from T34s the Germans certainly spent a great deal of effort festooning it with spare track links, concrete domes, and such. Its main fault was that it started life as an infantry fire support weapon and got drafted into the role of tank killer.

[YankeeDog]

According to the Achtung Panzer website, the "Saukopf" mantlet wasn't even introduced until Feb. 1944. Presumably, it wouldn't have become the more common configuration in the field until some months after Februrary.

If this is correct, this is a pretty important point; also according to AP, the earlier "boxy" mantlet was only 50mm frontal armor, which would make it easily penetrable by the Zis-5 at most combat ranges.

That mantlet represents a fair percentage of the StuG's frontal aspect. In CM terms at the very least, I would think that the presence of this significant area of 50mm plate would warrant modeling the earlier "boxy mantlet" 80mm Stugs as effectively having a "shot trap" similar to the early model Panthers.

Worth noting that, in order to engage an enemy tank, a StuG must present said enemy with an exactly zero degree angle shot at this mantlet armor.

Or maybe I'm wrong and this boxy mantlet was upgraded via bolt-on plates to 50mm + 30mm as the rest of the frontal aspect was? Some websites (incl. AP) seem to indicate that this front mantlet plate was sometimes upgraded to 50+30, but are unclear as to when, or how often. I would think adding that much weight that far out on the barrel would tend to mess up the gun system. . .

Worth noting that if the Feb. 44 intro date for the Saukopf is correct, by the time it becomes common, 85mm and higher Russian AFVs are also pretty darn common. By this time, the Russian ammo quality problems are also fixed, at least as CMBB models it.

Cheers,

YD

[MikeyD]

Every side in the conflict had awful prolems with their attempts to uparmor gun mantlets. The Russians wanted to do it with the IS-2, The Germans would've LOVED to uparmor their PzIV mantlets (as would all CM players). But they all ran into issues of overloading the gun trunnions, unbalancing the gun, unbalancing the whole turret! I do not recall ever seeing a photo of an uparmored early Stug mantlet, probably for that very reason. The box-shaped mantlet looks to be a major component of balancing the Stug gun on it mount.

[tools4fools]

Originally posted by YankeeDog:

Worth noting that, in order to engage an enemy tank, a StuG must present said enemy with an exactly zero degree angle shot at this mantlet armor.

True enough, but you better hurry up when that mantlet armor is at exactly zero degree pointed towards you...

It might be already a tad late aiming for that vulnerable part of the Stug front.

Myself, I would prefer not to have to try.

Marcus

****

[K_Tiger]

Aehem... the strengts of the Stug was more to avoid the Bullets insteed to stop them.

@yankee

A group of well defending Stugs would give you headaches, no matter if you attack with T-34/85 or else.

[YankeeDog]

@ tools:

True 'nuff; I certainly wouldn't be putting myself into the StuG's crosshairs just to get a flat shot at the mantlet!

HOWEVER, it would make a HUGE difference in CMBB if Stugs up to the IIIG (late)when the Saukopf comes in were modeled with the equivalent of the early Panther's "shot trap" to model the this thin mantlet armor. You still wouldn't want to take a StuG on 1-one-1 frontally with a T-34, but with local odds you'd stand a pretty good chance. Also, Russian 45mm AT guns would suddenly some chance of penetrating a Stug frontally at ranges around 700m; a range at which the StuG won't be able to spot the AT gun firing. Again, this makes a *huge* difference tactically.

@ Tiger:

No kidding. You mean Stug crews actually prefered to avoid being hit in the first place? I'm shocked.

And no argument that Stugs are still quite formidable when facing them with T-34/85s. My point was that T-34/85s a huge improvement over the T-34/76s when facing Stugs. You can frontally engage a StuG with 4 or 5 T-34s at nearly point blank range, and more often than not the Stug will win; the only way the T-34s win is if one of them manages a weak point, gun or track hit before they all get killed. Two T-34/85s will usually beat a StuG frontally if the engagement range is under about 700m.

Of course, in general you're always better off flanking Stugs, but sometimes terrain or supporting enemy units make this difficult, and having the *option* of eliminating a Stug by using a frontal attack with overwhelming local superiority makes a big difference.

Cheers,

YD

[Mr. Tittles]

Hold the presses.

The StuG investigation by the Military Gollege (Chobham) has an excellent cutaway drawing of a early StuG. The mantlet, like most mantlets, covers an already armored area in most cases. So the Box mantlet is not THAT weak. It would still have issues like a shot trap around it, etc.

I like the 'panther-weak-area' idea.

[K_Tiger]

@Yankee

It was more a Metapher....What i hade in mind, the Stugs were build to give a small Target...not jumping around to avoid the bullets

You have to stay on the carpet... "4-5 T-34...." this doesnt shed light one how the Stug perform....against singel, standard opponents.. And those flanking ideas always implement that you have more Stuff than your ennemy...

I`m with Mr. Tittles on the highly sloped parts... hard to defeat or better, the round first needs to get grip on the surface...

One question i have: The 80/0 surface is relativ small, doesnt it resist more compared to bigger armor plates like the one on the Panther glacis?

[YankeeDog]

@ Mr. T:

Yeah, I wondered if there was a second layer behind the Mantlet. At the very least, though, I would think an AP round that penetrated the mantlet, but was stopped by the backing hull armor would usually knock out the main gun.

@ Tiger:

Armor experts like Lorrin know much more about this kind of thing than I do, but as I understand it, generally speaking, smaller plates resist less effectively than larger plates due to edge effects -- on a small plate, it is more likely that a hit will land close to a free edge where edge effects come in to play.

This might also be something that should be considered in the future with the Stug -- generally speaking, it has a much more complex frontal area, made up of many smaller plates rather than a large, mostly continuous glacis. As such, it may be that the Stug was more suceptible to edge effect weak point hits than other AFVs. I think Lorrin is making this very point in (G) above.

Overall, it sounds to me that the Stug front should ideally be modeled as 80mm(-) -- kind of the opposite of the Tiger Mantlet, which is modeled as 102(+). Where the 102mm Tiger Mantlet is actually substantially thicker and/or backed in some places and so resists like substantially more than 102mm on a significant percentage of hits, the Stug front, while techically mostly 80mm, has many more bolt holes/edges than most frontal aspects, and so probably resists like significantly less than 80mm on a significant proportion of hits.

Cheers,

YD

[Mr. Tittles]

The early StuG shows that the gun mantlet shield overlaps another plate behind it which is also 50mm. Note that the gun mantlet is inset and sits behind the front driver plate armor.

[Mr. Tittles]

This shows the later L48 box mantlet. Is there actually another mantlet behind the front armor of this box also?

[Mr. Tittles]

Originally posted by YankeeDog:

@ Mr. T:

Yeah, I wondered if there was a second layer behind the Mantlet. At the very least, though, I would think an AP round that penetrated the mantlet, but was stopped by the backing hull armor would usually knock out the main gun.

Cheers,

YD

I would certainly agree that guns alignment would be thrown off and traversing and elevation gears damaged also. This also damages the counter balance mechanism. Guns can be thrown off trunnions too.

Just driving around a long barrelled gun messes up the alignment. Fine gear systems do not like to be back driven (moving gun barrel starts to reverse the gears).

The early StuG mantlet appears to be held on with U shaped brackets that look as if they are designed to give somewhat.

[Mr. Tittles]

The lighting here clearly shows that there would be a path to the very back armor behind the gun (50mm) on these box mantlet StuGs. Its a small area but still a weakness.

Edit: That area is actually part of the mantlet! Behind it is the front fighting coompartment wall (also 50mm). The main potential weakness would be the front of the mantlet box. Behind it may be the gun itself and a path to the interior. The pigs head mantlet would eliminate this weakness.

[ September 29, 2004, 08:18 AM: Message edited by: Mr. Tittles ]

[tools4fools]

Originally posted by YankeeDog:

HOWEVER, it would make a HUGE difference in CMBB

That's very interesting in my opinion.

In CM it would make a huge difference as we could calculate how are the chances to hit that vulnerable aera of this gun mantle and if we have that and that many T-34 we will win even in a frontal encounter...

This sort of thinking and calculating is as much Ueber as the whole Stug itself (or at least it is often called Ueberstug by some).

- would the red tankers have ever thought like this? doubt it very much. They would certainly not calculate their chances, rather prefer to manouver to the sides, no?

So at the end of the day it does not matter that much - do it like the red tankers - try not to go up front, but get to a position to get a side shot.

If you can't, just die in a honorable way.

Instead of asking for more chances of that vulnearble hit place chance.

Like the space between the mantlet and the front plate as in one of the pics above - sure a well placed lucky shot could fit in there - if it is a caliber that fits in there in the first place - but aren't we getting lost in the details?

Isn't the main point not to go up with a 76mm up front against those 80mm Stugs?

I think we do not need more predictable battle results and tricks and...whatever - even if those are based facts and absolutly historical.

At leat not at the present.

The more we get that kind of stuff the more we need the unpredictable in the game as well (which is real andh istorical as well, no?) Otherwise the game becomes a chess like thing were you can calculate everything.

How about the human factor? Sometimes tanks are cowering and retreating and people are complaining about that a lot. I think it is needed - even more often if we get all those bits and pieces we can calculate with.

I remember in the old CC series that squads and tanks started to act on thier own. Attack in a completly stupid way and get toasted (if not seen by the player and stopped). I loved this. They did someting real stupid on their own!

So yes, it would make a huge difference in BB. But it wouldn't in real life.

The more predictable tiny bits will be included the more unpredictable pieces have to come into the game as well - otherwise the predictable will be abused in an unreal way.

It's the same as using multiple 20mm to put heavy tanks out of action.

Do we need more of such?

[YankeeDog]

I can easily turn that logic on its head, Redwolf.

That is, in CM at present, German players *know* that for a large period of the war no common AFV-mounted weapon can penetrate a Stug at *any* range, excepting rare weak point hits.

I doubt that RL German Tankers had such specific knowledge about the capabilites of their frontal armor vs. Russian guns. Just as Russian tankers understandably did probably prefer to flank, German Stug drivers probably preferred to Shoot and Scoot, or engage from keyhole positions, rather than expose themselves to a hail of return fire from a large number of enemy tanks, even if they could limit their exposure to the frontal aspect.

But while Russian players learn very quickly to maneuver and flank if they want to win in CM, there is very little incentive for German players to limit the exposure of Stugs, at least frontally, for a large part of the war. Basically, as long as you keep an 80mm StuG facing the enemy, you can be pretty sure it's safe until bigger guns like 85mms start showing up.

If there was evidence in the historical record for this kind of near-invulnerability (as there is with the Tiger I), I wouldn't have a problem with it, it would be one of those interesting historical challenges that CM presents, just like taking out KV-1s in 1941 is when playing Germans, or dealing with King Tigers in 1944 as Americans.

So if the historical evidence supports the effectiveness of the Stug's frontal armor, I'll live with it in CMBB. In fact, I'll enjoy it. But I've read some pretty persuasive arguments that the Stug front armor is at least a bit overmodeled in CMBB.

To put it in your terms, the current modeling of the superiority of the Stug's frontal armor seems is way to "predictable", to me and if the physics and historical record warrants it, I thinks it would be better if the Stug front were perhaps a bit more vulnerable.

What I'm suggesting would, in fact, not be very deterministic, or "predictable" at all. In fact, it would probably result in a matchup very similar to Early model Panthers (shot trap) vs. T-34s or Shermans at close range. I've played Panther vs. Sherman matchups God knows how many times since CMBO, and I frankly don't have any idea how many Shermans you need engaging a Panther frontally to have a reasonably good chance of scoring that critical 'weak point' hit before the Panther knocks out all of your tanks. In fact, the answer depends on many factors, including but not limited to the exact range, the specific engagement angle, relative experience level, the specific type of Sherman involved, the LOS conditions, etc.

So yes, I agree that more unpredictability is good. The addition of AFV crew morale, and the possibility of "Knock-Out by Panic" is a great thing in CMBB is a great improvement. And I agree that the the model could be more unpredictable elsewhere (spotting is the single biggest area that could use more randmoness, IMHO)

And if the evidence warrants it (which I from what I've seen at this point it does), I would add to the "more randomness" wishlist an occasional, unpredictable vulnerablity in the Stug's frontal aspect.

But all this is a moot point. CMBB isn't going to be patched, so we're all wasting our breath. At least, until the next time BFC visits the East Front.

Cheers,

YD

[tools4fools]

YD,

not that I am against putting in a shot trap or whatever in a Stug front if this is historical.

But to me this is just another fine detail and I see lots of such details discussed here. Fine with me as well, after all they make for a more realisitc game and that's what we all like here, no?

I think battlefront is doing a good job here.

But what is way more important is the human factor who often screws up things.

Yes, the KO by panic is an improvement, yes cowering tanks are an improvement.

And maybe a Stug that gets hail of fire should retreat on his own faster. Maybe such things should depend even more on crew experience (Elite crew stands their ground longer if it makes sense, regulars retreat after a few hits, greens are completly unpredictable - most will run quick, some will stay as elite would as they don't realize what's going on.

Another thing is that panicked crews/units running away some 15 meters and then being completly uncontrollable and getting slaughtered... maybe a real "retreat immediatly coommand, only possible away from the enemy, should be possible for panicked and broken units?

Spotting is another issue, Borg type of course, but tanks spotting maybe as well especailly closed down without cupola. Have not done any testing, but they seem to see quite a lot anyway - but then maybe that is caused by Borg.

How would you want to implement something as mentioned by Carius like "Russian tankers often closing up and just driving forward". This is reading his book only but he describes often battles and actions where the Russians were fighting completly stupid and lost because of that. No, not that such behaviour exisited only among the Red tankers - I doubt some green Stug tanker with little training towards end of the war (or any period of the war) would do better.

Again experience could make a much bigger difference than it is in the game now. And maybe to have the option be forced to play more with mixed troops.

Maybe some "random experience" as in the rarity settings. That would mean if you buy a Tiger platoon you would probably get regulars, vets and maybe some elite mixed in if it was an "elite" unit and if you get Pz IV you will automatically get one or two greens, a regular and a vet maybe.

No such things like platoons of just regular/vets mixed. More variation. And yes, I know we can do that by chosing the troops ourselves this way - but wouldn't it better to have it as an option (like in rarity) - both players will have to cope with the same.

Such improvments are more important in my opinion (for all sides of course).

Or it is important that they are not neglected compared to those "technical issues" - I hope (and am quite sure) that a new game engine will have even more detailed armor model with variable sizes of turret fronts, etc, etc, as such defencies in the current model have been discussed here often - but as importnat is that those other factors are not neglected!

Otherwise the battlefield becomes to predictable.

Guess you get the picture.

Marcus

****

[YankeeDog]

No argument; BFC is doing a great job! :cool:

And more refined modeling of the strengths and weaknesses of AFV armor, Stug included, is indeed just one of a long list of potential improvements; I think all the ideas you suggest are good ones, and I'm sure we could add many more.

I think it's one of the indications of just how good CM is that it inspires so much debate about how it could be improved. I don't think any of use would put so much time and effort into advancing ideas here on the forum if we weren't so completely taken with the existing product.

I do think that the Stug armor vs. Zis-5 is an especially important part of the game model to get right, though, for no other reason that it happens to be a VERY common armor vs. armor matchup on the East Front. I'm a little dissapointed that BFC didn't tweak this in their last patch, as I think some pretty knowledgable forum members (specifically, Lorrin, JasonC, and Mr. Tittles) have made convincing arguments that the Stug frontal armor is at least a little bit too effective against the 76.2mm caliber as it is modeled CMBB. There seems to be some disagreement as to the exact degree of the overmodeling (or undermodeling of 76.2mm AP), and the specific technical reasons why, but that's details.

In BFC's defense, much of what we're talking about here was just surfacing on the forums around the time of the third, and final CMBB patch. I think if the discussion about this issue had been a couple of months farther along when the patch deadline came up, it's probably more likely that some kind of tweak would have made it into the patch.

Cheers,

YD