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jwatts
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David, yeah that's kind of what I have figured out from all my time lurking. I hate numbers and statistics, so it actually hurts my head to try to read all stats. I just tend to keep scrolling until I see a block of words with no numbers involved. With that said, I suspect this will be my last posting on this particular thread. I am more interested in real world tactics and expecially the in-game equivalents than in real world tests and statistics. Mr Kettler, once again, you really must stop this interesting practice of apologizing any time I pretend to be offended! I promise, I hear much worse insults from my good friends, anything you inadvertently might say to offend me will be forgotten by the next evening (alcohol kills brain cells). So au revoir to this thread, time to terrorize another with my weak attempts at smartassery and sarcasm.

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jwatts,

As noted before, acute insomnia doesn't improve my ability to notice subtlety in how you express yourself. Thus, it blunts my ability to separate the feigned from the real. As for the stats, I'm no mathematician myself, but they are important to understanding how best to employ the various weapons in the game. A few millimeters can mean the difference between a dead tank and a live one, a successful ambush or a waste of ammo and subsequent slaughter of your own troops. The line from the song "The Gambler" is apt here.

Andreas,

Am starting to think you've been pounding Perverse Pills. Please explain to me how it is that if the German 3.7 cm round is APHE, and all German APHE rounds from 3.7cm up are capable of wrecking tank and crew given partial/full penetration folowed by detonation, that the 3.7cm APHE somehow is not and that it doesn't follow that it can?

Jentz's quote on this seems straightforward to me.

In all calibers of 3.7 cm and above, the normal armor-piercing round designed by the Germans contained a high explosive filler with a delay fuze. Penetration of a British tank by a German armor-piercing shell frequently resulted in crew members being wounded as well as destruction of the tank by causing irreparable damage or by setting it on fire.
Regards,

John Kettler

[ January 25, 2007, 02:49 AM: Message edited by: John Kettler ]

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Originally posted by John Kettler:

Please explain to me how it is that if the German 3.7 cm round is APHE, and all German APHE rounds from 3.7cm up are capable of wrecking tank and crew given partial/full penetration folowed by detonation, that the 3.7cm APHE somehow is not and that it doesn't follow that it can?

I don't have to explain anything John. The quote simply does not say 'all German APHE rounds from 3.7cm up are capable...' - it is you who is saying that.

The quote says that all German rounds from 3.7cm up had APHE. Then it says that hits by (unspecified calibre) APHE frequently resulted in wrecking. That's all it says. You are making a connection that is not supported by the quote. It is an interpretation - yours. Mine is different.

All the best

Andreas

All the best

Andreas

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Originally posted by Andreas:

Then it says that hits by (unspecified calibre) APHE frequently resulted in wrecking.

Actually, what it says is that penetrations by "AP shell" (presumably APHE, calibre unspecified) frequently resulted in wrecking. Since the 37mm was profoundly unlikely to penetrate in the first place, it's behind-armour effects are rather moot.
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JonS,

Jarrett specifically refers to APHE in the novel to me form of "A.P.-H.E." The Jentz quote says that the normal AP projectile for German guns from 3.7cm on up "contained a high explosive filler with a delay fuze." If this isn't APHE, then what should we call it? Both you and Andreas seem to be splitting a nonexistent hair. The meaning of the passages is clear to anyone with even a working knowledge of the English language. I recap.

1. Projectile primary type is AP.

2. Projectile has an HE filler and a delay fuze.

3. All German AP projectiles from 3.7cm up use this type of projectile as the standard type.

4. This kind of projectile generally wrecks the tank and wounds the crew.

Q.E.D., it logically follows that if a German 3.7 cm APHE manages to pentrate, or per British OR partially penetrate, a given tank's armor plate and detonate, it has the strong likelihood of wrecking the tank and wounding the crew. Granted, it would be worse with a larger projectile because of greater fragment mass produced by penetration and subsequent projectile case disintegration, plus a substantial bump in the explosive force unleashed within the tight confines of the fighting compartment.

Regards,

John Kettler

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Originally posted by jwatts:

I am more interested in real world tactics and expecially the in-game equivalents than in real world tests and statistics.

Weapon capabilities to a great degree dictate tactics. Particularly in the sort warfare seen in North Africa between 1940 to 1943. Although I don't disagree that the contrast between AP-shell capability and AP-solid was probably not something that was occupying the thoughts of common soldiers.

Of course rendering a tank combat ineffective would be of paramount interest to the common soldier and his leaders. And the ability of AP-shell fire to set a tank or tanks on fire has consequences that transcend the immediate tactical considerations of a small unit leader. If I win a tank battle and hold the field, I have the ability to recover and repair my own tanks – thus I can maintain the operational combat power of my formation. On the other hand if I win the same battle and hold the field, but all of my AFVs have been set on fire from AP-shell fire, I may not be recovering much of anything and my unit’s combat power dwindles. Weapon capabilities and weapon effects can therefore shape both tactical and operational aspects of war.

For the wargamer playing the one time kamakazi game in which a scenario is removed from any context within time and space, there is little interest in whether or not a tank burns after being knocked out – aside from the game graphics look ‘cooler’ if the wreck is burning and vomiting plumes of smoke. The tank is knocked out and requires no further attention. No need to consider recovery etc. The player is removed from “real world” tactical thinking.

Conversely dudes playing a campaign game might be very interested in whether a tank burns or not. Moreover a campaign game would -- in theory -- have context within time and space, and tanks that burn are not likely to be recoverable. The player doesn’t get back burned-out tanks when they fight the next tactical battle of the campaign. Their combat power dwindles.

Best Regards

JD

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Originally posted by John Kettler:

The meaning of the passages is clear to anyone with even a working knowledge of the English language.

So, JonS and I don't have a working knowledge of the English language?

Why don't you just accept that different interpretations of the passage are possible?

e

Originally posted by John Kettler:

4. This kind of projectile generally wrecks the tank and wounds the crw.

Since you have such a great working knowledge of the English language, why are you not capable to quote Garrett correctly?

Your recap is not what the report says. Frequently is not identical to generally, unless we are supposed to have a working knowledge of Kettler's English, as opposed to Queen's English.

All the best

Andreas

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Not to put too fine a point on it John, over the last few years you have repeatedly shown an appaling lack of judgement, discernment, and ability to interpret reality. If you told me the time I would be forced to ask for a second opinion.

You may think your analytical facilities are just dandy - and once again regale us with tedious anecdotes about breifing the Joint Chiefs, or the President, or the King of Mars, or sumfink - but most people would disagree with that assessment.

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To attempt to help out here a bit, John, although whether it will help is yet to be seen, let's break down the quote:

In all calibers of 3.7 cm and above, the normal armor-piercing round designed by the Germans contained a high explosive filler with a delay fuze.

No problem so far, right?

Penetration of a British tank by a German armor-piercing shell.....]

Ok...now, while the "normal" German AP round might contain HE, this does not mean all of them did. In fact the use of the word "normal" implies more than one type. So it is not specified here whether penetration is achieved by AP shot or AP-HE. (Ok, ok, it probably is referring to APHE. Just not certainly.)

.....frequently resulted in crew members being wounded as well as destruction of the tank by causing irreparable damage or by setting it on fire.
Hence you don't know exactly what is causing this damage.

Furthermore, even if we accepted that what is being talked about is exclusively AP-HE, there is no comparison given between the effects of APHE and AP shot, making the quote, on its own, meaningless as a comparison, because there simply isn't one.

Lastly, the quote says damage was "frequent". That is a rather elastic term. It could range from "sometimes" for 37mm, to "nearly always" for 88mm, giving an overall term used by the author of "frequent". You cannot take the statement to imply equal performance for all calibres; there is simply no basis for it.

The quote may have been intended to mean exactly what you think it does. But it does not conclusively say it, on a number of levels.

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McIvan,

There are two basic German AP projectile types, or PzGr, with the normal one, PzGr 39, being APHE and the special one, PzGr 40 (no explosive charge, hence AP shot), being technically known as HartKern(?) which I loosely translate as being "hard kernel," AKA Tungsten, APCR or HVAP to us.

Since, by definition, a shell carries an explosive charge, whereas shot does not, it logically follows, does it not, that when the quote refers to "armor-piercing shell" it is referring to APHE?

Given this, it should be immediately apparent that the Jentz quote refers to PzGr 39, or APHE. Otherwise, the quote wouldn't read "armor-piercing shell," especially in conjunction with the sentence immediately preceding it. The Jarrett quote, regarding German APHE from 4.7cm on up, confirms that this interpretation is correct. In case there is any further doubt, please refer to the British conclusions regarding the lethal effects of formerly German, reworked 75mm APHE on German tanks. The conclusion? A tank so hit was a tank destroyed.

Given the above, I maintain that I DO know which projectile variety is being described.

Turning now to the question of how often tanks and/or crews get clobbered, given penetration

and detonation by German APHE, where I come from, "frequently" means more often than not, thus can reasonably be interpreted as more than 50% of the time. That, in turn, makes it the usual or general outcome.

From the sum total of the various quotes I've seen, the general conclusion, one borne out by British OR, is that German APHE, given partial/full penetration and detonation, typically wrecks the tank and wounds the crew, whereas 2 pdr. fire typically leaves a repairable tank and largely unscathed crew.

An example of this is a picture I've seen repeatedly of a DAK Panzer IV/D? in which the driver's plate has taken two 2 pdr. hits (fresh holes clearly visible), but the driver is still on the job, albeit with a head bandage. Do you consider that a likely outcome, given the information assembled, for a tank penetrated by one APHE projectile which penetrates and detonates, let alone two?

This is not to say, though, that there is no difference between having a 3.7 cm round and an "88" go off inside the tank. Rather, we're talking degrees of ghastliness, with the "88" up at the top of the ghastliness scale. Even so, if the puny 3.7cm can manage to penetrate and detonate, you're likely to be out a tank and a chunk of the crew.

Andreas,

That was not a slam on either your or JonS's English skills. Rather, it was meant to illustrate the obvious and straightforward nature of the logic and evidence therefor. As for Jarrett, I have quoted him directly where applicable and provided multiple confirmations of claims I made regarding him and his contributions to the war effort, drawing upon sources ranging from the Green series ordnance volume to the statement of a Grant unit commander at Gazala.

Regards,

John Kettler

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Originally posted by John Kettler:

McIvan,

There are two basic German AP projectile types, or PzGr, with the normal one, PzGr 39, being APHE and the special one, PzGr 40 (no explosive charge, hence AP shot), being technically known as HartKern(?) which I loosely translate as being "hard kernel," AKA Tungsten, APCR or HVAP to us.

That somes it up pretty well. I have as yet to see a solid shot version of pzgr. for the 37mm Pak, Flak or Kwk -- aside from APCR.
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Well, yes, if you believe that fuzes are ordered into production without checking that they function properly. It would be nice to think that British defence procurement didn't do things like that, but...

The Admiralty created testing criteria that was as good or better than anyone of this period. However, the test conditions were reflective of assumed battle conditions. No one was anticipating the sorts of engagement ranges seen at Falklands, Dogger Bank or Jutland.

Shells were being tested at relatively low obliquities. Mostly 0-degrees testing from what I have seen. This is indicative of anticipated combat ranges of 10,000yards or less. The engagements ranges in actual combat were pushing 15,000 to 20,000-yards where AP shells were plunging down at angles of 20 to 30-degrees. Shells striking heavy cemented armor components were breaking up at these sorts of obliquities. The bursting charges were either not functioning, or they were prematurely detonating before complete perforation.

But this wasn't simply an issue with British shell fire. The same sort of issues were occurring with High Seas Fleet AP-shells. It's just that those of use living in Countries where English is the primary language get exposed to more British source information. And perhaps come to the conclusion -- rightly or wrongly --that this was a problem restricted to Royal Navy shells. And of course British documentation has survived the ravages of time a bit better than German sources.

Nope, I'm afraid the Hogg piece I quoted is my only source for this (and he doesn't specifically say "trials", although I can't imagine where else "experience" would come from).

There are a couple of things in the WO32 series that look as if they might be helpful, and I'll try to remember to take a peek at them next time I'm at the PRO, but that will probably not be for quite a while.

All the best,

John. [/QB]

Not a big deal. My life and/or pride is not balled up into this trivia. It is more curiosity regarding how the British developed their particular philosophy on this issue.
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Jeff Duquette,

Now, that is interesting information! I've long known the British shells at Jutland had major problems, so major ISTR a national scandal over BB and BC shells not detonating and practically deflagrating even when they did. I believe problems were found with both the fuzes and the fill explosive. Even hazier recollection on the latter points to corners being cut on the explosive fill, as in not up to spec.

My brother, Ed Kettler, did extensive dev work for

"Fear God & Dread Nought" a WW I version of the Clash of Arms Games Command at Sea game system for miniatures. Given what you've told me, I believe I'll ask him how these issues were handled in his game.

Am glad that you "get it" regarding my German APHE discussion. Given some of the replies I've gotten from others, I was starting to think I was arguing in Hittite!

Regards,

John Kettler

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Originally posted by John Kettler:

Jeff Duquette,

Am glad that you "get it" regarding my German APHE discussion. Given some of the replies I've gotten from others, I was starting to think I was arguing in Hittite!

Regards,

John Kettler

Oh I get it. I got it from the start. My mind was made up sometime ago, but I see no point in continuing along with the arguing. The British had one philosophy; a number of other countries had a different philosophy. Neither is "wrong". I mean AP-solid shot will generate fragmentation upon penetration, and one doesnt have to worry about predetonation on spaced armor -- plus solid shot will perforate more armor than shell.

But than AP-shell will generate the same sort of fragmentation upon penetration -- plus the shell -- assuming its bursting charge works -- will generate fragmentation(+). Moreover it gets the splinters from the armor plate spalling and perhaps the projectile nose breaking up, plus it gets fragmentation from the ass of the shell exploding after perforation.

I look at it like this: Two 37mm projectiles are fired at a target -- one AP-solid and one AP-shell. Perforation for both shot & shell generates anywhere from say 10 to 100 effective fragments from plate spalling – or whatever. And of course these are just arbitrary numbers.

Bursting Charge: If it functions following perforation even a small caliber shell will generate additional fragmentation within the confines of a tank.

The bursting charge is – as has been pointed out -- small in a 37mm pzgr. It’s only about 13grams or some such thing. But even a very small caliber HE shell like 20mm HEI will generate some 100 to 150 effective high velocity fragments upon detonation. More specific -- the bursting charge in say 20mm M97 HEI is smaller (it’s only about 8-grams) than the charge contained in 37mm pzgr. But M97 will generate on average over 100 effective fragments. I would therefore assume the 37mm pzgr’s burster could generate perhaps as many, perhaps more effective fragments as the much smaller charge in 20mm M97.

To me the math is that simple. Both AP-shot & AP-Shell get fragmentation from perforation of the plate. The AP-shell gets bonus fragmentation if the bursting charge functions. But it is not worth it to me to try and convince anyone of this. Folks are gonna’ believe whatever they want. I mean we all have to find our own way to truth.

Good luck

Jeff

Sorry -- HEI is actually M97, not M95. My bad. M95 is 20mm AP.

[ January 27, 2007, 07:25 AM: Message edited by: Jeff Duquette ]

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jwatts,

You're welcome! Lone Sentry has lots of goodies like that. In fact, in the Russian view of fighting Tiger Is thread on the CMBB Forum, I posted another great link. My favorite part is the infantry test for tank traffickability. You'll see!

Jeff Duquette,

Apparently, the classic U.S. 20mm round used from the Korean War through the Vietnam War for air-to-air was pretty anemic in the blast department, so much so that on detonation, there was practically no side spray of fragments at all.

Our weaponeer at Hughes showed me the data himself.

Basically, they barely emerged laterally but were overwhelmed by the forward velocity component.

Regards,

John Kettler

[ January 26, 2007, 07:41 PM: Message edited by: John Kettler ]

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Originally posted by jwatts:

... While discussing questions on the book, I might also ask, about how many of the accounts of "panthers/tigers" are true, in regards to fighting in NW Europe? Every time they run into opposition, it is only 88mm guns, Tigers, or Panthers. Obviously SOME of this is exaggeration due to FOW, but what kind of numbers of Ubercats are we talking about the Brits ACTUALLY facing in Normandy/Caen/Falaise?

Personally I think the Tiger or 88 is also a "slang" affair among western allied troops and simply means something dangerousis shooting at you. At normal combat ranges (<1400m) it doesn´t really matter much whether your M4 Sherman is hit by the long 75 of a Pz-IV, Stug or Panther, since all of them most likely will penetrate and kill your tank. Same for the 88 which probably just means a dangerous gun, no matter if it´s a real 88 (Flak, Pak or KwK) or any of the common german Pak (75 and russian 76). A crew sitting in a Churchill model surely will have a different opinion about the fine differences between the performance a 75L48, a 75L70 and any 88 since the latter 2 are more of a danger than the first.

German reports aren´t always accurate about enemy tank models either. In particular on the eastern front where designations of enemy tank models may vary largely. Sometimes you read about heavy tanks, sometimes you read a 52 ton model , sometimes an exact designation as KW (not always telling of 1 or 2 model) or a Stalin. At the start of Barbarossa in 41 also the T-34 models where described as beeing heavies. Same goes for russian light and medium tank models. Oftenly there isn´t even be made a difference between Tank and Assault Gun type vehicles. I can imagine since german infantry learned to fear the T-34 quite early, that many infantry unit battle accounts report of its presence more oftenly than would be actually correct (a larger amount were probably also of the T26, BT and KW type). Confusions between T-34 and KW might have happened widely too. Both are very dangerous to infantry (and early german tanks).

Off course this is a sort of generalization and just a guess from my side, but yet worth to consider when reading those accounts just telling of opposing Tigers and 88. Also depends upon particular reporting unit (tank or infantry), style of report (official unit reports, stylish personal accounts ect.) and particular ToW, where a Brit unit with previous experience from the desert war surely has a better idea what an 88 (Flak) is and what not. Mentioning more Tigers and Panthers in reports up the chain of command might also have served the purpose to encourage delivering valuable Fireflies or 76 Sherman quicker and in more numbers, who knows. There´s many reasons not to take those Tiger/Panther and 88 reports always for granted. Truth is and numbers always tell, at least 50% of reported german tanks/AFV´s in 1944-45 were those with the 75L48. Considering reliability, favor goes even more to non Panther and Tiger stuff in the front lines.

AFAIK there also wasn´t much of real differentiation between those oftenly reported german Bazooka Boys, which more oftenly were probably Panzerfaust equipped infantry and not those with the Schreck.

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Originally posted by John Kettler:

Apparently, the classic U.S. 20mm round used from the Korean War through the Vietnam War for air-to-air was pretty anemic in the blast department, so much so that on detonation, there was practically no side spray of fragments at all.

Our weaponeer at Hughes showed me the data himself.

Basically, they barely emerged laterally but were overwhelmed by the forward velocity component.

Regards,

John Kettler [/QB]

Not to diverge off into la-la land again, but what "classic" 20mm round are you refering to, and what US Aircraft was firing 20mm in air-to-air over Korea? F-86 used 50-cal.

As to the classic round being "anemic" -- I suppose it is a relative thing. If your weapons expert was expecting the same sort of fragmentation associated with a 105mm HE round exploding, than yes, 20mm is very anemic ;) But 37mm pzgr isnt a 105mm HE projectile. It’s bursting charge weight is greater than, but closer to that of 20mm M97 HEI.

Now I have the data for 20mm M97 HEI, see attached. I'd be interested in seeing this other data you are referring to. Might be interesting to compare whatever projectile your dude was referring to. The M97 projectile data shows an average of 111 effective fragments ranging in velocity from about 1500-fps to about 891-fps.

20mmm97fragmentationsx8.th.jpg

We’re not gonna get anywhere broadsiding with anecdotes. So what is it in your last post that advances the discussion toward some sort of resolution? Are you now saying that 37mm pzgr. bursting inside of a tank would be anemic?

I’m not interested in arguing semantics; playing forum games; or lowering myself to the use of debating tactics. My intent and point in bringing the M97 to the table was to try and put some numbers to this thing. Possible fragmentation associated with a projectile with a bursting charge of weight of “X” (M97). We have another projectile (37mm pzgr) with a bursting charge weight of “Y”. Y > X so in my mind the projectile with “Y” bursting charge weight might be expected to generate as many fragments as the projectile with a bursting charge weight of “X”. This is an obvious simplification as bursting charges often employed in AP-shells consisted of higher brisance material than that utilized in HE projectiles. But this last bit only implies this mode of comparison is that much more conservative. If you have a better mouse trap for quantifying this thing than lets hear it.

This isn’t in my mind a complex problem. You have perforation fragmentation and you have bursting charge related fragmentation. Solid shot doesn’t get any bursting charge fragmentation.

Perforation generated fragmentation may be minimal for well manufactured armor – it may be as low as “one” effective fragment – i.e. the projectile itself. Ductile failure and petaling of the plate. If I have “one” effective fragment from perforation of good quality armor, and I subsequently introduce an additional 100-fragments from a bursting charge exploding, than yes the effect of 37mm pzgr is relatively speaking "highly destructive". I’d go so far as to imply that in this case it would be considered “very highly destructive”. Moreover the difference in P(k) between one fragment entering the crew compartment and 100+1 fragments entering the crew compartment is considerable.

On the other hand if the armor shatters at the point of impact into a thousand high velocity splinters -- as what apparently happened on occasion when a 2-pdr AP perforated Italian armor -- than introducing 100-additional fragments from a bursting charge detonation will not likely alter P(k) by an appreciable amount.

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The USN's F9F's packed 4 x 20mm M3 cannon during hte Korean war.

The F-86 was not the only fighter.......so much so that the very first jet-jet engagement of the war resulted in a Mig being shot down by an F9 smile.gif

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Jeff Duquette,

Regarding the U.S. 20mm round, late model F-86s had 4 x 20mm cannon, rather than 6 x .50 cal. MG.

Have seen one 20mm armed model myself. I don't know the nomenclator, but I believe the basic round dates back to at least the Korean War and that there was no major change until some sort of ammo redesign was done in the 1970s about the time the F-15 came into service. I don't know, offhand, the vintage of the M97 HEI.

I'm not trying to be either vague or elusive. Rather, I'm working from 22-24 year old memory of an explanation I didn't grasp right away even back then. What I recall clearly, though, is that whatever 20mm round our weaponeer was describing

had such weak sidespray that I was told the resulting fragments would wind up in a small circle around the axis of projectile flight. ISTR, too, that he said that the sidespray was so weak that you could essentially trap the sidespray with your hand wrapped around the projectile. Mind, your hand would be cut up!

I say the above not to denigrate my own argument about APHE lethality, but because our weaponeer singled out that particular 20mm round as, well, an execrable and miserable excuse for a weapon. I believe he said they might as well have not fitted it with a burster charge.

I basically agree with your argument regarding differences between what the secondary missiles are for AP shot vs. APHE. Both displace a plug and spall coming through, but only APHE explodes inside, attacking the tank's interior and the crew with combined blast and frag effects, in very close quarters. I think, too, that your brisance argument is well taken.

Since you're looking for data, here's a wartime German assessment of several different antitank cannon, using a variety of projectiles, against a Matilda II.

http://www.lonesentry.com/manuals/artillery-in-the-desert/appendix-a.html

Sidebar

According to this, the German 2 cm. autocannon on

the Panzer II, SdKfz 222, etc. was capable of firing airbursts to ruin the day of troops in foxholes, trenches, heavy frontal cover and the like.

http://miniatures.de/html/int/shells-german.html

Hogg, in THE GUNS:1939-45, p. 73 lists the burster charge for the 3.7cm Pak-36 as being "less than half an ounce of PETN, desensitized with wax" and characterizes the burster charge quantity for weapons of this size as "derisory." Where Hogg and I part ways, and I have immense respect for the man and his work, is in his assertion that the difference to the victim between shot and shell in this small caliber is indistinguishable, since the OR and field observations show that wasn't the case. In fact, as I've shown, the difference between AP shot and APHE is quite considerable, with lethality markedly favoring the latter.

I have dug quite deeply in my way less than exhaustive references and other than Hogg, have naught to show for the 3.7 cm APHE's exact explosive load, but I do have a data point for comparison. From Hogg's AMMUNITION, p. 149 in the drawing of the 3" shell with Projectile, fixed, A.P.C. M62 with fuze BD M66A1 and Tracer. Explosive filler is listed as 0.14 lbs. Explosive "D."

ISTR that back in the CMBO days someone posted a thread on explosive fills for APHE projectiles. Might've been you. If you have/can get access to the relevant volume of German Explosive Ordnance,

the highly detailed info you seek should be there.

Failing that, try Mark Diehl's German ammunition series in the long defunct AFV-G2 magazine.

Regards,

John Kettler

[ February 10, 2007, 03:04 PM: Message edited by: John Kettler ]

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Originally posted by Jeff Duquette:

To me the math is that simple. Both AP-shot & AP-Shell get fragmentation from perforation of the plate. The AP-shell gets bonus fragmentation if the bursting charge functions. But it is not worth it to me to try and convince anyone of this. Folks are gonna’ believe whatever they want. I mean we all have to find our own way to truth.

But merely counting the number of effective fragments doesn't give you the whole story. It also matters how they are distributed in space (viz. John K's own example of the poor side-spray from a 20mm round) and in time.

As to the time element, according to Nathan Okun's page:

http://www.navweaps.com/index_tech/tech-020.htm

...the minimum delay to be expected from a mechanical fuze is of the order of 0.003 sec; I don't know what the actual fuze delays from PzGr39 would have been, but I imagine that a mechanical fuze would not have an extended zone. If anyone has any information, please let me know.

Taking this figure, and assuming a projectile moving at 2,000 feet per second, this corresponds to a distance travelled before detonation of six feet. I find it hard to imagine where, inside a WW2 AFV, one could trace a shotline six feet in length without hitting all sorts fo things.

Of course the residual velocity after penetration could be much less, in fact could be anything down to zero (if it embeds in the armour). Given the reduced distance of travel before detonantion, and the reduced forward throw of the fragment spray, I would expect the relative value of a burster charge to increase as the residual velocity of the projectile fell. We also know that the fragmentation produced by penetration of non-exploding projectiles increases as the square of the velocity. So I would expect both the value of APHE and the need for it to decrease as residual velocity increases. In other words, I would expect that it might have some value in converting marginal cases to kills (viz. Jarret's mention of incomplete performations), but, especially in small calibres, I see no reason to disbelieve Master Gunner Hogg when he says that it isn't worthwhile.

The passages from Jarrett John K seems to have agreed are his source are, let us be clear, not OR studies (MELF stands for Middle East Land Forces, btw, John), they are personal observations. When I read them I took them to be an indication of the need to improve ammunition stowage to prevent "brew-ups", and on re-reading they still seems to say the same. British tank desgners took up a policy to deal with this problem, adding armoured stowage bins and declining to stow ammunition above the turret-ring. If the passages were really intended to convey the message that APHE is a crew-killing wonder-weapon, then I am at a loss to explain why nobody in the OR or tank design communities ever (as far as I know) called for APHE to be adopted for land service, or why the supposedly fearsome destructive qualities of APHE mysteriously escape mention in all the personal recollections of British tank crew members (Joly, Crisp, Tout, Foley, Wilson, Farrell, Hills, Dyson -- there are quite a few of them).

All the best,

John.

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