The german tank be weaken or the Russian ammo be strengthen in the CMRT?

[YankeeDog]

YankeeDog, do you have any numbers that support that? I do not agree.

Why, yes, actually I do:

http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1164&context=usarmyresearch

A period U.S. Intelligence translation of the WWII USSR Ballistics tables for the A-19 gun, now declassified for your enjoyment.

In relevant part, you will note that on full charge, direct lay at a target the same altitude as the muzzle, The 122mm A-19 firing BR-471 AP Tracer has a time of flight to 1000m of 1.3 seconds, with a trajectory apogee of 2.1 meters above the muzzle. So, on a perfectly aimed 1000m shot, the shell leaves the barrel on a slight climb, reaches a maximum altitude of 2.1m above the muzzle somewhere between 500-600m from the gun, and then drops back down to muzzle height just at 1000m.

I'll leave it for you go find the equivalent data for the 75mm KwK42 L/70. What you're going to find is that the overall trajectory is flatter, but the actual difference in apogee above the gun barrel between the two trajectories is fairly small; only a fraction of a typical WWII tank's ~3m height.

So I'd say it's pretty safe to conclude that trajectory "flatness" is not particularly strong factor in the relative combat accuracy of the A-19 122mm vs. the KwK42 75mm at =>1000m range. I would expect the KwK42's flatter trajectory to offer some advantage in first round hit %, but only a small one. Assuming arguendo that the KwK 42 achieved dramatically better first round hit % under combat conditions at 1000m, there must be strong factors beyond just "flatter trajectory."

Push the range out to 1500m or more, and I would expect the KwK42's better ballistics to become a more significant factor.

And remember: The Panther is a bigger target than an IS-2. Both taller and wider, and this will cancel out some of any accuracy advantage the Panther might have in a head-to-head matchup.

Another note: Comparing gun accuracy, hit % and penetration figures from different nationalities is problematic unless you have corrected for test conditions and tabulation methods. The Soviets and Germans tested and tabulated things like gun accuracy and projectile penetration very differently, so you have to check the underlying conditions before you can compare Soviet test data to German test data.

Similarly, tactical and doctrinal philosophies were also very different, so you have to be careful when comparing figures like maximum recommended engagement range, etc.

Regards,

YD

[Erwin.Rommel]

Just did some further tests about the T-34/76 and MarkIV(J), range is about 600m. all hits on the hull front achieved completely penetration. see the picture below

[Erwin.Rommel]

The penetration on the glacis was achieved by the 85mm APBC which is not around the bow maching gun or the edge of the armor. How to explain?

[Bastables]

is it any different with one of the FH armour PIV's? As the Ausf J is a RHA which was much less effective at inducing shatter of comparatively brittle Soviet AP rounds.

I may be misremembering but I'm sure that you were better off taking PIV's with FH armour than the ausf J in CMBB. On the Western front games it was reversed as the RHA was a bit more effective, I seem to remember when CMBN first came out that ausf J were more survivable vs Sherman 75s than the earlier FH PIV's like the H's and G's.

[Battlefront.com]

Yes, there are some mismatches between round type and armor type for specific vehicles in given years used by different nations. It's pretty complicated and I don't remember which vehicles and ammo types complimented each other and which ones didn't. Just that sometimes having face hardened armor was a good thing, sometimes not depending on what was being shot at it and the range.

Steve

[Sixxkiller]

I think what is usually the case with the fans here is that they get the game and expect the same results all the time to come from this game. The engine just deals with probabilities and that in itself will certainly not always produce realistic expectations. There are so many variables that go into the physics sub-routines that who is to actually say with every shot if the round has lived up to the realism you expect.

[costard]

The penetration on the glacis was achieved by the 85mm APBC which is not around the bow maching gun or the edge of the armor. How to explain?

Erwin, that plate took a beating before it was penetrated. I wouldn't be saying this is an unrealistic result.

[Vanir Ausf B]

That Panther is an ausf G, which as we know has at least a chance of flawed upper hull armor in the game. We just don't know how flawed. At some point this week I will run some tests that will hopefully give us a general idea.

The T-34/76 vs PzIV H example is hard to judge because there is a lot of conflicting data about the performance of the Soviet F-34 cannon. WW2 Ballistics gives 3 different possible muzzle velocities for that weapon, and 2 varieties of APBC ammunition (BR-350B and BR-350B "Special"). I have also seen reference to a BR-354B that was reportedly introduced in 1944. We can only make educated guesses at what data CMRT uses. In CMBB the muzzle velocity was 680 m/s, the highest of the 3 possibilities. At that velocity WW2 Ballistics lists BR-350B penetration against RHA (Pz IV J armor) at 600 meters as 73mm. CMBO modeled Pz IV J and H armor at 95% quality, which would resist equal to 76mm* (I don't have the CMBB or CMAK armor quality figures, unfortunately). That would give a penetration probability of 16-28%, depending on whether you go by US or Soviet data. So if *all* hits on the upper hull are fully penetrating that may be a cause for concern.

* The CMx1 games all modeled the Pz IV upper hull at its official thickness of 80mm so my assumption is that CMx2 does also. A thickness of 83mm would be more accurate as that was closer to actual production thickness. CMAK was the first CM game to acknowledge the extra thickness of the Panther glacis plate beyond it's official number, modeling it at 83mm. WW2 Ballistics lists the measured Panther and Pz IV upper hull armor plates at 85mm.

[Bastables]

Erwin, that plate took a beating before it was penetrated. I wouldn't be saying this is an unrealistic result.

Yeah, not sure if it's modeled but if one were inclined, the penetration of the glacis is within one and a half diameters of a previous strike meaning it could be taking edge effect into account.

IRRC USA Army tests ignored such penetrations as it was understood that the edge effect of previous strikes would play a role in subsequent strikes.

[Vanir Ausf B]

Erwin, that plate took a beating before it was penetrated. I wouldn't be saying this is an unrealistic result.

In reality, no. But keep in mind that, unless it has been changed, CMx2 does not model cumulative armor damage. The decals are just eye candy in that regard.

[Bastables]

In reality, no. But keep in mind that, unless it has been changed, CMx2 does not model cumulative armor damage. The decals are just eye candy in that regard.

Bugger was hoping that they'd added in "dynamic" free edges.

[Erwin.Rommel]

is it any different with one of the FH armour PIV's? As the Ausf J is a RHA which was much less effective at inducing shatter of comparatively brittle Soviet AP rounds.

I may be misremembering but I'm sure that you were better off taking PIV's with FH armour than the ausf J in CMBB. On the Western front games it was reversed as the RHA was a bit more effective, I seem to remember when CMBN first came out that ausf J were more survivable vs Sherman 75s than the earlier FH PIV's like the H's and G's.

the T34/76 in 1944 used the blunt nose BR350B APBC, according to lorrin's book, the russian APBC have better porformance with FHA than RHA(no better than the APCBC used by german and other western countries),

[Erwin.Rommel]

I think what is usually the case with the fans here is that they get the game and expect the same results all the time to come from this game. The engine just deals with probabilities and that in itself will certainly not always produce realistic expectations. There are so many variables that go into the physics sub-routines that who is to actually say with every shot if the round has lived up to the realism you expect.

I don's expect the same results all the time, I just don's expect the impossible results that indicated by various resouce of WWII armor and ammo(especially the Lorin's book, Lorin play a very important role in the establishment of the armor system used by CM) happen in the game.

[Oddball_E8]

I can't say I've seen anything near what is described here.

I constantly get raped by the german armour and when I do manage to knock one out in an "even" match (76mm vs IV, 85mm vs panther or 122 vs KT) it's usually with a partial penetration that seems to be more luck than anything else.

Very rarely do I get full penetrations anywhere on the "strong" parts of the panther and IV.

Although the impact marker is the same for a partial as for a full penetration... so it looks the same.

[Kanonier Reichmann]

Just wondering. I don't have the game as yet but have people who do run any quick tests to see if the T34/76 is able to at least occasionally penetrate the Stug front at ranges of 800 metres or less? I seem to recall that was a major point of contention in the old CMx1 Barbarossa to Berlin title.

Regards

KR

[kipanderson]

Erwin, hi,

Just did the tests and am not getting “impossible...” results.

You probably know all this, but just for fullness and for those less unhinged than you and I on the subject... will give some detail I am sure you already know.

So... just to get it out of the way.. do always use the Early T34/76 to be sure not to fire tungsten. I am sure you are doing that anyway.

The MarkIVJ at 600m.... blasted away at it with 76mm APBC and found the following results. From top to bottom.

Turret Front penetrated with ease as it should be.

Superstructure Front Hull resisted as it should. Most were straight ricochets, just reported Hit and where it hit. Some resulted in armour flaking, I think CM calls it Armour Spalling. But overwhelmingly it was a case of Hit report and where hit with no adverse effect except to morale.

Upper Front Hull penetrated as it should be. Due to APBC’s exceptional penetration at high strike angles the Upper Front Hull offers no protection to 76mm APBC ammo at any range.

Was waiting to witness a Lower Front Hull hit, quite a few to get a sample, but witnessed non in the time I did the test so cannot say. In test the rounds don’t always hit where you want them to .

However... did do a quick test with StugIII Mid at 600m.. just to see if there is a problem generally with 76mm APBC ammo. Achieved no penetrations. Not on lower hull, upper hull or front superstructure. There was some Armour Spalling but otherwise all just ricochets. All as it should be.

So in conclusion based on my tests.. 76mm APBC ammo is penetrating or failing to penetrate exactly as that great Lorrin book would predict against MarkIVJ and StugIII Mid. It certainly would have been nice to witness hits against the Lower Front Hull of the MarkIV... but did not in these tests today. One day hopefully when I have time and just keep going .

Panther.

85mm APBC ammo has a penetration against vertical plate of 121mm at 500m. Panther’s glacis plate gives a protection in equivalent millimetres of vertical plate when struck by an 85mm APBC projectile of 160mm.

But.. as you will know both the A and G models of Panther had flawed armour in their glacis plate. I know not what that flaw is modelled as by Charles. You certainly did hit the plate numerous times and there is range of outcomes in there.. Bell curve and all that .

Just to confirm what others have said.... Panther’s Lower Front Hull plate of 65mm gives a protection against 85mm APBC ammo of 114mm in equivalent millimetres of vertical plate. As mentioned above... 85mm APBC ammo penetration at 500m is 121mm. So Lower Front Hull is vulnerable out to 1000m if D and A models and if G model out to 2000m.

Would have been nice to have witnessed a MarkIVJ hit on the Lower Front Hull in my test, but that is statistics for you... but with that qualification all currently seems OK.

All very interesting stuff..

All the best,

Kip.

[kipanderson]

Hi,

Quick add on...

With tungsten projectiles fired the 76mmm guns MarkIVs and StugIII are very vulnerable out to around 700m – 800m.

All the best,

Kip.

[Vanir Ausf B]

Thanks for testing the 76mm, kip.

But.. as you will know both the A and G models of Panther had flawed armour in their glacis plate.

Note that according to the manual, only the ausf Gs have flawed armor in the game. I have done small scale testing vs late ausf As and have yet to see 85mm APBC do more than scratch the paint on the glacis plate.

[Redwolf]

Look at the date. Kursk. The Soviets were still using mostly uncapped AP rather than the more effective APBC. And their metallurgy was less advanced in '43.

But whether the ballistic cap is more or less effective depends on the target's armor composition (more effective against face-hardened IIRC), and on the angle.

[Volksgrenadier]

German testing at Kummersdorf showed that the 122 mm gun could not penetrate the glacis plate of the Panther at all at 30 degrees, could penetrate the nose at 100 m and the turret mantlet of the Panther at ranges up to 600 m.[98]

The Panther's 75 mm gun could penetrate the front of the IS-2's turret at over 1000 m, the drivers front plate at 1000 m and the hull nose at 1000 m.

http://en.wikipedia.org/wiki/Panther_tank

[Erwin.Rommel]

Thanks for testing the 76mm, kip.

Note that according to the manual, only the ausf Gs have flawed armor in the game. I have done small scale testing vs late ausf As and have yet to see 85mm APBC do more than scratch the paint on the glacis plate.

your tests in accordance to my result. all the penetration on the glacis was achieved with the Ausf G

[Erwin.Rommel]

But whether the ballistic cap is more or less effective depends on the target's armor composition (more effective against face-hardened IIRC), and on the angle.

Just note: the "ballistic cap" should be replaced by the "capped"

[YankeeDog]

German testing at Kummersdorf showed that the 122 mm gun could not penetrate the glacis plate of the Panther at all at 30 degrees, could penetrate the nose at 100 m and the turret mantlet of the Panther at ranges up to 600 m.[98]

The Panther's 75 mm gun could penetrate the front of the IS-2's turret at over 1000 m, the drivers front plate at 1000 m and the hull nose at 1000 m.http://en.wikipedia.org/wiki/Panther_tank

Again, you have to check testing conditions -- note that the Kummersdorf tests used a target Panther that was facing at 30 degrees off the gun's line of fire, so the projectile had to deal with horizontal armor slope in addition to the vertical armor slope. This makes a big difference. You will find other tests that show front glacis penetrations by the BR-471 APBC on the Panther front Glacis out to 1000m or so *if* the engagement aspect is flat.

With the German Kummersdorf tests, I've also never seen definitive info on what ammo they were using, and when the test ammo was captured (or, ideally, manufactured). This matters considerably because Soviet AP ammo improved in quality steadily throughout the war and even within a specific ammo type, shells manufactured later in the war were often higher quality than earlier stuff. So if the Germans were testing with 1943 vintage ammo, they'd probably get very different results than if they were using 1944 vintage ammo.

If you do a broad canvas of what's out there, you will find some tests of the A-19/D-25 vs. the Panther that show relatively easy penetration of the Panther Glacis and Turret, at least on a flat aspect, out to at least 1000m. And you will find other tests that do not. So to me, the interesting question is *why* these tests results are so different. Ammo quality? Quality/condition of target? Differing test conditions like the aforementioned 30 degree side aspect of the Kummersdorf tests? All of the above and more, I suspect.

Overall, though, I would say it's at best unproven that that BR-471 APBC should, excepting rare weak point hits, fail to penetrate the Panther front Glacis at 1000m. There is an arguable case that at least with normal horizontal engagement aspect, there should be some decent chance of penetration.

[Alchenar]

Guess what was translated from the Russian archives today!

http://tankarchives.blogspot.ca/2014/04/panther-trials.html

[Erwin.Rommel]

Do the same test again an again, still see the same results.

these are the early version of T34 I used in my tests with no APCR

these two pictures shows the superstructure been penatrated.

This picture also shows a very strange hit in the tests, how to explains this?