Long 88mm lacking punch?

[Ari Maenpaa]

Now when I have the Jentz’s book…

In CM the German 88/L71, which is often said to be the best AT-gun of the war (Yes, I know about 128/L55 and that’s not the point here), seems to be lacking some punch. This is the conclusion I made when comparing it’s ingame armor perforation info with data given by Thomas Jentz in “Germany’s Tiger Tanks, Tiger I & II: Combat Tactics”.

For comparison:

Penetration at 30 degrees when using Pzgr.39:

______CM_____Jentz_____

range

100m 177mm 202mm

500m 165mm 185mm

1000m 151mm 165mm

2000m 121mm 132mm

The difference is quite considerable (about 10%)

Conflicting with this, CM’s armor perforation data for the guns of Panther 75/L70 and Tiger I 88/L56 seems to be almost identical with Jentz.

Yep, I have read some previous threads about penetration values in CM and BTS have stated that for the game they used their own mathematical models and not some flawed test data from books.

Because I’m quite “green” on these kind of values, I would like to get this right from the start for myself. Is it that 88/L71’s values are somewhat exaggerated in Jentz’s book and BTS has hit the bullseye in CM with their physics models. Or is it possible that a little correction is needed in CM?

Or for some unimaginable reason, are they both right?

Also one can say that this difference may not be very important in CM, but surely these same values will be used in CM2. In the East Front this difference will have much more consequences.

I would be very interested to hear some informative opinions, thank you.

Respecfully, Ari

Ps. There’s probably more questions coming after I have finished my Jentz.

[This message has been edited by Ari Maenpaa (edited 08-21-2000).]

[howardb]

Don't know any numbers but I had a battle against a Jumbo76 the other day, it bounced 5 88L71 rounds before I got it.

[PzKpfw 1]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Ari Maenpaa:

For comparison:

Penetration at 30 degrees when using Pzgr.39:

______CM_____Jentz_____

range

100m 177mm 202mm

500m 165mm 185mm

1000m 151mm 165mm

2000m 121mm 132mm

]<HR></BLOCKQUOTE>

Hmmm have to check into this I never bothered to check the 8.8 cm L/71 data. They may be useing another refrence's data, or what they _feel_ is right.

Regards, John Waters

--------

"Go for the eyes Boo, go for the eyes!!".

[This message has been edited by PzKpfw 1 (edited 08-21-2000).]

[Guest Mr. Johnson-<THC>-]

yeah, I agree, hehehe. Does not make much diffrence right now, but come CM2, I know I'll be crying when I fight any of the KV series. Call in the Jabos.

[willys]

Don't know about CM because I only have the demo and it isn't represented in the two included scenarios, but.....In Close Combat III this is one of my major gripes. Even with the small scale of the maps (about 500 meters max) Tigers regularly bounce shot from the T34's hulls and 88 guns become almost pointless because the initial starting range between the two forces is too small. This leads to the gun being less effective than it would have been in reality because the tanks can get beads on it pretty quickly once it is spotted. In reality the 88 would have probably picked off several of those rusky tanks before they ever got that close....Also the shortened maps tend to make the Soviet 122 and 150 gunned tanks more powerful as tank killers because, again accuracy at these ranges gives them more of an advantage. Again, in reality a longer engagement range would allow the high-velocity Tiger and Panther guns to be much more accurate at say, 1500 meters or so.

[willys]

Some more thoughts on this post....Perhaps this is why the Russian numerical advantage in this game is not as greatly exaggerated as it could have been...so as not to create an unplayable game from the German perspective? One more thought, only fifteen units per side? This seems too limited....

[Guest Germanboy]

<BLOCKQUOTE>quote:</font><HR>Originally posted by willys:

Again, in reality a longer engagement range would allow the high-velocity Tiger and Panther guns to be much more accurate at say, 1500 meters or so.<HR></BLOCKQUOTE>

Provided you have LOS, of course. Which is a bit more of a problem in Western Europe than in the Eurasian steppe or Arizona. Unless you are sitting on top of Bourgeoubus (sp?) Ridge or in Holland, you will be quite hard-pressed to find such long-distance LOS for DF weapons. Which sucks of course if you have these nice guns, but life just isn't fair. So this is a very different issue from the penetration capability of the gun per se.

------------------

Andreas

[willys]

Andreas,

Agreed. The point I was trying to make here is that weapons effectiveness, in some instances, seems to be be toned down significantly in CC3 to facilitate the games purposes. By the way, did you happen to know that I live in Arizona or did you just mention that by coincidence?

[Guest Germanboy]

<BLOCKQUOTE>quote:</font><HR>Originally posted by willys:

Andreas,

By the way, did you happen to know that I live in Arizona or did you just mention that by coincidence?<HR></BLOCKQUOTE>

Checked your profile before posting. Try to get into the habit myself. If it had said that you live in eastern France, I would not have bothered to post, b/c than my post would certainly have been pointing out the obvious. This way it probably has, but I just wanted to make sure that the lay-of-the-land issue is not confused with the other point.

------------------

Andreas

[The DesertFox]

<BLOCKQUOTE>quote:</font><HR>Is it that 88/L71’s values are somewhat exaggerated in Jentz’s book and BTS has hit the bullseye in CM with their physics models. Or is it possible that a little correction is needed in CM?<HR></BLOCKQUOTE>

Naaa,

Jentz´s values aren´t exaggerated. Actually the data he presents is basing on german tests conducted with target material laid back at an angle of 30 degrees, consisting of rolled homogenous plates with the following hardness dates : 81-120mm (thickness)= 279-309 BNH and 121-150mm = 235-265 BNH.

If there are correct data around somewhere, these data are. Furthermore you have to keep in mind that due to the fact that the PzGr 39 carried a high explosive charge with delay fuze (the filler) it was of annihilating effect to the crew inside the tank.

Because of this filler it was sufficient to optain a partial penetration and the explosive charge could complete the destuction of the crew.

In contrast the effect of the PzGr 40 (tungsten core) was basing solely on whatever kinetik energy remained in shot fragments when it shattered and/or fragments of armor plate broke off after the hit.

However 1944/45 distribution of 7,5cmL/70; 8,8cmL/56 and 8,8cmL/70 PzGr 40 was VERY VERY VERY rare if at all (that´s a point of discussion even under historians and not absolutely clear).

To the values in CM: I´m sure Charles can answer why they differ from published sources. However in CM it makes no difference to gameplay AFAIK, so IMHO it may be not a big issue for BTS.

If you like Jentz "Tiger Combat" book, you will love his Panther book and his book on Armoured Warfare in Northafrica. You wont be dissapointed.

Helge

------------------

Sbelling chequed wyth MICROSOFT SPELLCHECKER - vorgs grate!

- The DesertFox -

Email: desertfox1891@hotmail.com

WWW: http://www.geocities.com/desertfox1891

[willys]

Helge,

From my understanding of the materials I have read regarding German use of tungsten-cored rounds, production fell off dramatically after about 1941 because of the lack of available wolfram to create these projectiles. It is probablt pretty well known to the grognards on here that the Germans created a highly successful squeeze bore gun in the 28 mm size that was made even more dangerous with the use of tungsten rounds. The gun was highly portable and could be setup with an extremely low profile. I've got a picture of one being crewed in a book I have called "Weapons of the Waffen SS". It was sort of an oversized super-antitank rifle.

[Paul Lakowski]

The 88 L71 should be able to penetrate 60mm RHA @ 60o @ 2km range, more than enought to penetrate the T-34 Glacis.

Why where the 88 figures reduced when , as I understand it , German penetration figures were used as the standard?

[willys]

Ari,

I have figures from another source that match up closely with what you have from Jentz. And this was using only solid-core shot! It goes on to say that with APHE rounds there have been recorded cases of T34's being knocked out at ranges of up to 3500 meters....thus my point about CC3's accuracy.

[Ari Maenpaa]

DesertFox,

Yep, I think that I will acquire all the WW2-books written by Jentz. He seems to know what he is talking about and I haven't heard/read nothing negative about his texts.

This forum is likely to be the right place to ask opinions about him as a historian.

willys,

Well I bought CC3 a long time ago and I also ditched it a long time ago. It was nice for a short moment but differed too much from reality for my taste. As they say: CC2 is the best in the series.

That said I hope that the western front alone won't be the best front in CM series.

And then to the topic:

After a second thought I think that the lower values for 88/L71 matter even now, because in many matches I, playing the Germans, have faced the whole arsenal of Super Pershings the Americans ever had. Every centimetre of penetration is needed then. Was I able to say it straight-faced?

And every time I introduce CM to a new player at least the first game is with some ridiculously big stuff. No talk of sense has changed that. People want to try the biggies.

Also, and these are purely selfish reasons, I would like to be able to use all the tank versus tank penetration tables in Jentz's books as a direct reference when playing CM. That really would make the game feel ultra realistic

It would also be nice to know that when the long 88 kills a tank it's pure history happening in the game. This is how it was 60 years ago and this is how it is now. Of course this applies to the whole game and to all it's guns.

And lastly: it's somewhat puzzling when the ingame values for guns of Panther and Tiger I match almost perfectly, but for 88/L71 they don't.

It makes you to ask

Ari

[Dittohead]

Long Live Jentz!

[Guest Big Time Software]

I do not doubt the authenticity of Jentz' numbers for the 88/71. However I think they are wrong nonetheless. They are considerably overstated.

How do I reach this conclusion? The simple physics behind it. Combat Mission does not use "penetration tables" or charts to determine armor penetration. Instead it uses the mathematical equations described in "Penetration of Armour Plate" originally by (British) Ordnance Board Subcommittee of the Armour Piercing Projectile Committee (reproduced by U.S. Dept. of Commerce National Technical Information Service #PB91127506).

These equations do a wonderful job of matching up with virtually all published "penetration charts" that I've come across, save for one: the 88/71. This tells me that something was not "constant" across the testing data. It's possible that the 88/71 was tested against plate of a differing hardness, that "success" of penetration was judged by a different standard, or simply that a bit of propaganda was being put forth.

To see why this is so, we'll take a look at Jentz' numbers for the lower-velocity 88 L/56, mounted on the Tiger I in comparison to the 88/71. But first, let's isolate a variable. To get an idea of how much additional striking velocity increases penetration, let's compare some of Jentz' numbers that are not in contention: the 75 L/70 (Panther gun) with the 75 L/48 (PzIV gun). This is a simplified example, but it gets the point across.

<PRE>

Name 75 L/48 75 L/70 Difference

Muzzle Velocity (m/sec) 740 925 +25%

100m penetration 99mm 138 +39%

500m 91 124 +36%

1000m 81 111 +37%

1500m 72 99 +38%

2000m 63 88 +40%

</PRE>

Note how the 75/70 has a velocity 25% greater than the 75/48, and penetration about 38% greater. Now let's compare the two 88mm guns.

<PRE>

Name 88 L/56 88 L/71 Difference

Muzzle Velocity (m/sec) 773 1000 +29%

100m penetration 120mm 202 +68%

500m 110 185 +68%

1000m 100 165 +65%

1500m 91 148 +63%

2000m 84 132 +57%

</PRE>

The 88/71 is about 29% speedier than the 88/56, about the same as the difference between the two 75mm guns shown above. And yet Jentz' figures would have us believe that the penetration increase in this case is a whopping 65% instead of the 38% we'd expect from the earlier example!

This is a simplified example, of course, and one cannot expect purely linear results. But this clearly demonstrates that Jentz' 88/71 numbers are not even in the right ballpark.

Note also that Jentz' figures for the 88/71 are greater than those for the Jagdtiger's massive high-velocity 128mm gun! This just does not square with reality.

Charles

[This message has been edited by Big Time Software (edited 08-22-2000).]

[PzKpfw 1]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Big Time Software:

I do not doubt the authenticity of Jentz' numbers for the 88/71. However I think they are wrong nonetheless. They are considerably overstated.

<HR></BLOCKQUOTE>

Jentz's numbers are not his, they come from German wartime test data. & i'm going to point out that the formula used by the British in the 1950 report concerning angle equasions is incorrect, as Robert Livingston discovered.

I don't know if that effects CM penetration or not, nor am I saying it does. The 1950 report was based on what they knew then about penetration, and thats where the error occured in the formula.

I am not a mathamitician I will point that out freely now what I have learned I was taught by Robert,Paul, Rick etc. I also commend BTS for actualy useing the report.

I'm also going to add some example data from a very faded zeroxed hand written letter I recieved from Jim written by another concerning the British wartime penetration estimates based on their tests of German guns, vs their standard 250 BHN test plate: in ( )'s is the German test results, vs their standard 300BHN test plate: all results at 500yrds @ 30^:

7.5 cm Kw.K 40 L/48 739m/s

500Yrds - 106mm (92mm)

7.5 cm KwK. 42 L/70 730m/s

500yrds - 105mm (91mm)

8.8 cm KwK. 36 L/56 737m/s

500yrds - 124mm (103mm)

Notice the penetration diference in the British results?, German plate was about 10% more resistant per mm then US or UK plate at 250 & 255BHN, this also boosted German penetration vs US & UK armor.

Now some of you are saying look at the L/48, L/70 results, according to numerous sources including Jentz the Penetration & m/s data for the German guns & ammunition is clearly wrong. Ie, the KwK.42 at 500ms according to German wartime test data did 124mm using 925m/s Pzgr.39 APCBC vs 300BHN plate.

And heres where it gets dicey concerning penetration data as their is speculation the Germans overstated their penetration test results, as well as speculation that German penetration data was obtained useing top grade ammunition, which performed much better then what crews were issued in the feild.

Notice the m/s in the British results this was their m/s with the ammunition in question.

What does all this gibberish say, it says that basicly no penetration was exact due to difering conditions, varying plate BHN & quality etc, and that each country came up with differing results on the same guns.

Does this mean that the above data from the letter is correct or Charles values he used are incorrect or correct or the German wartime data is fudged, Or that my conclusions from deciphering a faded zeroxed hand written 10 page letter are correct, or incorrect, I honestly have no idea.

I'll leave what the 8.8 cm Pzgr.39 could or couldn't do to Charles, Paul, & others to ponder, but it does point out theire are discrepincies in all the test data for each country, and their are no carved in stone penetration numbers.

Regards, John Waters

--------

"Go for the eyes Boo, go for the eyes!!".

[This message has been edited by PzKpfw 1 (edited 08-22-2000).]

[The DesertFox]

Hey cool Charles,

That sounds reasonable to me. I just did some maths myself with the following formula:

where mp = mass of projectile (kg);

V = velocity of the projectile at impact (m/s);

t = thickness of armour perforated (mm);

d = diameter of projectile (mm); and

C, n = constants.

I choose the advanced formula for APCBC:

and the result I optained was that in case of the 75mm APCBC (6,8kg) and increase of the velocity of 25% is leading to an increase of armor penetration of 36%.

In case of the 88mm APCBC (10kg) an increase of the velocity of 29% (773ms-1000ms) is leading to an increase of armour penetration of 40%.

That tells me that indeed the data presented by Jentz for the 88/L71 does not seem to follow this AFAIK commonly accepted rough formula presented above. Maybe the germans used RHA plates of different quality for the tests.

But I have to second Johns statement that there definitively are no carved in stone penetration figures. Each country did different tests with different parameters that makes it hard to compare them. You have to look at them more as to an approximation and to keep sceptical if something doesn´t fit the whole picture. There is no black and white, more various shades of grey.

The only problem I see here with accepting penetration data which base on PRIMARY material (german tests in this case) and in an other case not accepting PRIMARY material out of the same source (we have to keep in mind that it isn´t Jentz who cranks them out. He is quoting them from primary sources) is calling into question the whole lot of data which went into the game. Who draws the line (BTS of course), and can we call the data in the game realistic ? The answer is NO, but we can call the data a reasonable approximation which is close enough to published sources to give a relistic feeling to the user. It´s a game after all and no realism simulator, and as long as there don´t creep up real flaws it´s fine for me.

BTW: to anyone who does not already know, David Honner has done a wonderful job presenting tons of penetration data and background information on his website. Pay him a visit at http://www.wargamer.org/GvA/

Helge

------------------

Sbelling chequed wyth MICROSOFT SPELLCHECKER - vorgs grate!

- The DesertFox -

Email: desertfox1891@hotmail.com

WWW: http://www.geocities.com/desertfox1891

[This message has been edited by The DesertFox (edited 08-22-2000).]

[This message has been edited by The DesertFox (edited 08-22-2000).]

[Paul Lakowski]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Big Time Software:

This is a simplified example, of course, and one cannot expect purely linear results. But this clearly demonstrates that Jentz' 88/71 numbers are not even in the right ballpark.

Note also that Jentz' figures for the 88/71 are greater than those for the Jagdtiger's massive high-velocity 128mm gun! This just does not square with reality.

Charles

[This message has been edited by Big Time Software (edited 08-22-2000).]<HR></BLOCKQUOTE>

Well if you don't believe Jentz try Ivan Hogg his figures are within a couple of mm of Jentz's figures, and if you don't believe them we have a problem here.

The problem with formulas is that the more you simplify data presentation the more info you lose. The ordnance board report covers APCBC up to around 2800 f/s while the 88L71 reaches 3300 f/s .

You old timers on this forum like to tell every one to 'search'. Well alot of us research , so I will point you in the right direction.

The search word is called

" Transitional Velocity" or "hydro dynamic Transitional Velocity" and its impact on the "plastic wave velocity" of the material and the mode of penetration . Believe me the difference of if penetration is above or below the Transitional velocity is critical!

[The DesertFox]

<BLOCKQUOTE>quote:</font><HR>willys said: Helge,

From my understanding of the materials I have read regarding German use of tungsten-cored rounds, production fell off dramatically after about 1941 because of the lack of available wolfram to create these projectiles.<HR></BLOCKQUOTE>

That isn´t the whole truth. From 1941 the germans shifted more and more tungsten to the production of higher caliber ammo. At first to the production of 5cm PzGr40 and then to the 7,5cm PzGr40 and the 8,8cm. Until in 1943 nearly all production of tungsten cored ammo stopped due to the shortages.

To the 28mm you mentioned: I guess you are referring to the s.PzB 41, wich was indeed a surprize for the Brits when they discovered that germany was using sqeeze bore guns in 1941 in NA. I don´t know much about it except that some special adaptions were made and it was issued to the Fallschirmjäger and used in greater quantities on the Eastern Front until the whole Panzerbuechsenconcept was skipped when they rendered virtually useless.

Helge

------------------

Sbelling chequed wyth MICROSOFT SPELLCHECKER - vorgs grate!

- The DesertFox -

Email: desertfox1891@hotmail.com

WWW: http://www.geocities.com/desertfox1891

[Ari Maenpaa]

Charles,

Thanks for a very detailed and down-to-earth explanation. That was a pleasure to read. And I appreciate your attitude to be ready to make these things clear.

PzKpfw 1, DesertFox,

Ok, point taken here, there’s no absolute penetration values in existence. If I want my own carved in stone values, I would have to attain those guns myself and personally do some test shooting.

Paul,

You seem to have some untapped knowledge on these perforation values, but could you perhaps be more exact. I know nothing about “Transitional Velocity” or “hydro dynamic Transitional Velocity” and it's impact on the “plastic wave velocity” of the material. Huh?

I’m novice here, so…

does the long 88’s grenade break some speed barrier after which it can penetrate more steel than the ammo of smaller guns (e.g. it exceeds so called transitional velocity?)? Doesn’t the speed of the grenade slow down during it’s flight? Wouldn’t there be a clear speed limit under which the grenade’s ability to penetrate armour enormously decreases? Surely I’m lost with this case.

Maybe an additional explanation with some examples? Would a stand/bear comparison between 88/71 and the 90mm gun on Super Pershing give any concrete facts. At least their performance in CM seem to be very close.

Maybe there are similar cases with US or UK guns (76mm and 17 pounder for instance)?

Should I be asking these things from my psychologist?

Ahhh, your informative accounts makes an enjoyable reading. But as it often happens, answers only bring more questions.

Ari

[This message has been edited by Ari Maenpaa (edited 08-22-2000).]

[Lee]

So Paul, you are saying that by the 88 going 3300 fps it might well

be going so fast that it makes the standard penetration calcs the Brits

are using not give quite an accurate result? Seems possible, assuming

that something significant changes when that sort of speed is reached.

I assume that this is where the "transitional velocity" and it's affect

on the ability of the structure of the armor to resist penetration

comes into play.

Do you have any hard figures for this effect that could account for the

difference between the German test results and what the Brit equations

would predict? Because, naturally, Charles would need something

solid before such a change in the 88 could be justified. I'd love to see

the performance of the 88 be as accurate as possible (as with all guns)

and I'm curious to see if the German test figures were somehow

right after all.

[The DesertFox]

<BLOCKQUOTE>quote:</font><HR>Do you have any hard figures for this effect that could account for the

difference between the German test results and what the Brit equations

would predict?<HR></BLOCKQUOTE>

LOL! The test results don´t fit the formula, ergo the test results are wrong ?

Actually I would see it vice versa. Formulas are a sorry substitute for hard data and this example clearly shows the problems involved when trying to fit the real world hard data into a formula. The non ability to describe a phenomenon with a certain formula not necessaryly means that the phenomenon doesn´t exist.

Try to do the comparison I did just for fun with David Honners formula with 2 other guns. Or compare the data like Charles did. Try to compare the 75L/24 with the 75L/70 and see how silly the outcome is. Does that mean the data for the 75/L70 are faulty ?

BTW: If you use the very rough formula at David Honners site you have to use the velocity of the shell in the moment of IMPACT and NOT the muzzle velocity. <G> Velocity drops from the moment the projectile leaves the muzzle, so unless you know the velocity at 100m, 500m, 1000m etc. you cannot use the formula.

Anyone who has these data ? No this question wasn´t serious

Helge

------------------

Sbelling chequed wyth MICROSOFT SPELLCHECKER - vorgs grate!

- The DesertFox -

Email: desertfox1891@hotmail.com

WWW: http://www.geocities.com/desertfox1891

[Paul Lakowski]

<BLOCKQUOTE>quote:</font><HR>Originally posted by The DesertFox:

LOL! The test results don´t fit the formula, ergo the test results are wrong ?

Actually I would see it vice versa. Formulas are a sorry substitute for hard data and this example clearly shows the problems involved when trying to fit the real world hard data into a formula. The non ability to describe a phenomenon with a certain formula not necessaryly means that the phenomenon doesn´t exist.

Try to do the comparison I did just for fun with David Honners formula with 2 other guns. Or compare the data like Charles did. Try to compare the 75L/24 with the 75L/70 and see how silly the outcome is. Does that mean the data for the 75/L70 are faulty ?

BTW: If you use the very rough formula at David Honners site you have to use the velocity of the shell in the moment of IMPACT and NOT the muzzle velocity. <G> Velocity drops from the moment the projectile leaves the muzzle, so unless you know the velocity at 100m, 500m, 1000m etc. you cannot use the formula.

Anyone who has these data ? No this question wasn´t serious

<HR></BLOCKQUOTE>

Helge is ofcourse right hear...if the facts don't fit the theory , you don't chuck the facts , you modidfy the theory to inculde the facts or you chuck the theory.

For more info on 88mm velocity see the thread '88mm ballistics'

 [url="http://www.tanknet.org/ubb/Forum1/HTML/000314.html"]http://www.tanknet.org/ubb/Forum1/HTML/000314.html[/url] 

[/HTML]

At this point I need more time to study the results, but several things are clear....the shape and hardness of the ogive has a direct baring on penetration perfromance more so than velocity. The narrower and harder the tip the longer the delay in the onset of the 'transitional velocity'. It seems the this is the division between 'modern erosion' type penetration and 'normal' penetration.

I can post Jpegs to that site so I'll focuse on working some thing out there.

[PzKpfw 1]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Big Time Software:

Note also that Jentz' figures for the 88/71 are greater than those for the Jagdtiger's massive high-velocity 128mm gun! This just does not square with reality.

Charles

<HR></BLOCKQUOTE>

Charles I missed the above last night . Their is no trully definative penetration data for the 12.8cm L/55 gun. Ie, the most common data I have seen used is from Chamberin & Doyles "Encyclopedia of German Tanks of World War Two".

12.8cm L/55 fireing Pzgr.43 APCBC 845 m/s @ 30^

100ms - 187mm

500ms - 178mm

1000ms - 167mm

1500ms - 157mm

2000ms - 148mm

Now their is an an 12.8cm Pzgr. 860 m/s APC round as well but the APCBC listed above had better over all performance.

And their are higher penetration figures from Spielberger, Hogg, & Senger und Etterlin Ie, Hogg puts the 12.8cm penetration @ 212mm @ 500ms @ 30^ @ 1000 m/s; while Spielberger & Senger und Etterlin put the m/s @ 920.

Now I'm curious Charles as their seems to be some major disagrement concerning 12.8cm penetration among some very respected armor historians, while they all use basicly similar 8.8cm L/71 penetration data, what source data did CM use to model the 12.8cm L/55 m/s & penetration .

Regards, John Waters

----------

"Make way evil, I'm armed to the teeth and packing a hamster!".

[This message has been edited by PzKpfw 1 (edited 08-22-2000).]