rexford

Many German tanks met in France used face-hardened armor, and our book identifies armor by type as well as thickness and angle. Allies use APCBC in France almost exclusively, little or no AP fired by anybody. Russians fire rounds without armor piercing caps, which may be reason why Germans stayed with face-hardened armor through late 1944. Russian penetration drops against face-hardened armor. CM and CM2 implications? All armor on German tanks is not homogeneous, so need two sets of penetration figures. Actually need four in CM2, cause Russians fire AP and APBC from many guns, both without caps and each having drastically different slope effects. Some panzers use homogeneous armor in some areas and face-hardened in others. See the complication to do it right? CM2 would also have to use random choice to determine if tanks carried AP or APBC, since early IS-2 tanks appear to often carry one or the other. 122mm AP can't penetrate good Panther glacis at any range, 122mm APBC can at good range. Initial Russian tests and combat show that 122mm AP gets no penetrations. Then they meet poor Panther armor and some penetrations occur with regularity. So CM and CM2 need to randomize Panther glacis armor quality, rest of Panther tends to be good quality so quality factors change going from glacis to rest of tank. 122mm APBC penetration against poor Panther glacis is way beyond 2500m. Some of these things are not as simple as they seem. 17 pounder APCBC penetrates more face-hardened than homogeneous, smaller rounds penetrate about the same or less face-hardened. U.S. 76mm APCBC has collapsible nose and isn't so good as might be expected against face-hardened. Our book presents penetration data against face-hardened and homogeneous armor, where data is available or can be reasonably estimated.

I posted some graphs from the book on the Saumur site at http://musee-des-blindes.intranets.com/login.asp?link= Look under book update thread. Slope effect graphs for AP rounds against armor sloped at 0° to 60° from vertical, as function of T/D ratio. Used this info to show that 122mm AP could not penetrate Panther glacis with good quality armor. And this is what Russians found when IS-2 tanks first went into combat. Lots of bounces. All the time. Then they found that penetrations would occur inside 650m range with AP ammo. Armor quality varied a lot, quality factor is not a constant for Panther glacis. Flaws in Panther armor reduce armor resistance by quite a bit. Saumur site has some of our results on this. The Yahoo! Tankers site has our table of contents for book and one slope effect curve for AP rounds (no caps of any type). I will be posting the book table of contents on Saumur tonight, in about ten minutes.

Book is all about armor and penetration and hitting things. Nice drawings and graphs and tables and plenty of numbers, which may show why the root of numbers is "numb". If basing broad decisions on silly little millimeters is not your cup of tea, this may not be for you. The book is sort of a reference on penetration data and armor stats, and how to calculate armor resistance for comparison to penetration data. And why T34's blow open so easy when the armor thickness and angle is so good. The T34 front hull, 45mm at 60° slope from vertical, actually provides 20% more resistance than the Tiger driver plate based on calculations that only consider thickness and angle. How can this be? Say it ain't so! That's when armor hardness steps in and Mister T34 tips his hat (has the turret thrown off after a hit) to Tigers, and Panthers, and Marders, and 75mm Pak, and whatever else hits it within some pretty impressive ranges. Same for Sherman. 50.8mm at 56° from vertical, about 20% more resistance than Tiger 100mm plate. But along comes flaws and the resistance goes way down, like Mister T34. If you like to crunch numbers a little or a lot, this book would be good. The problem is how to accept payment and how to mail the thing. The book will be between 25 and 30 American dollars postpaid. An international money order costs how much? 11 American dollars, maybe. So the book would cost about 38 american dollars for 200 pages (100 pages but double sided). 10 point font so plenty of words per page, or numbers, or whatever. If you don't like to read the graphs and tables can be used and figured out without being chained to a desk for endless hours and days. Book is bound but not hard binding. I would appreciate comments, input and suggestions on payment methods. If we accept checks in foreign currencies there is a payment on this end. Then we'll decide and post order info. Thanks for responses.

Bumpity bump bump. Had to do this to get thread back to number one again.

Oops! Forgot to say that the major German tanks in Nord Afrika had face-hardened frontal armor, like PzKpfw IIIG-L and IVF-G. So having face-hardened penetration data for Allies is a must. One simply can't live without it if they game North Africa.

APCBC is very effective against face-hardened armor since the armor piercing cap with the flat nose has a tiny air space just above the main projectile nose. Face-hardened armor defeats ammo by cracking the nose, and the AP cap shifts the initial impact from the nose to the shoulders and spreads it out more. 75mm APCBC from Sherman penetrates 88mm of homogenous armor at 100m but 102mm of face-hardened armor. British 2 pounder AP without any caps penetrates about 85mm homogeneous at 0 yards and 66mm face-hardened. One of the interesting things the book will discuss and have data on is German use of face-hardened armor on most tanks and SP vehicles, even during 1944 on Western Front. PzKpfw IVH, Panther A, Tiger II, StuG IIIG have face-hardened armor in critical places. PzKpfw III goes without saying. Book will present, in our unhumble and exaggerated opinion, the best available single source on face-hardened armor penetration and tank protection in the world when it comes to Nord Afrika. Based on our researches and highly accurate speculation based on the tiniest fragments of data and imaginary flights of fancy, we have put together face-hardened penetration data for all major projectiles used by British and U.S., both AP and APCBC. And we have assembled the best analysis in the universe (and beyond, if one counts other dimensions), for spaced armor and layered plates, which presents the single best resistance figures for PzKpfw IIIH (32mm over 30mm), PzKpfw IVG (30mm atop 50mm) and PzKpfw III with the 20mm spaced from 50mm face-hardened. (CM shows PzKpfw IVG as 70mm front hull, an error that cries out for change!) Now, who can argue or throw sarcastic comments at an honest assessment of our essentially perfect and all-encompassing work? 30 years in the making, months in the writing, hours from publication. And minutes until I send this post in to CM. And seconds until I think of more trash talk to throw your way. And not to be outdone, we have exceeded past claims for 75mm HE fired from Sherman 75mm and German 75L24, which merely had it besting 90mm and 88mm HE in effectiveness (accuracy against ground points and fragment generation). All of this, and more, is in the book. This book will dramatically change the scope and content of armor research and day dreams at work, and we urge you all to strongly consider jumping on the band wagon before it leaves for points unknown (something like the Twilight Zone). Your assessment of German tanks will never be the sane, ah, I meant same, again.

Lorrin Bird here. Book will be finished and bound this week, ready to go next week. Still can't find Russian penetration data against face-hardened armor. British tests of German 75mm APCBC, U.S. 76mm APCBC, British 17 pounder and Russian 76.2mm BR-350B APBC at 610 m/s impact against British armor (0° impact) were tracked down and compared to data in our book. Very close match. German 75mm APCBC outpenetrates U.S. 76mm APCBC at 610 m/s by 13% when heavier and larger size of U.S. 76mm round is factored out of comparison. Russian 76.2mm round penetrates 75mm, compared to 101mm for German 75mm and 90mm for U.S. 76mm. 17 pounder APCBC penetrated 107mm. If 17 pounder APCBC had an HE filler and cavity instead of being solid, penetration would drop to 95mm or less. Seeing that 17 pounder is larger and heavier than German 75mm, the above data shows that German ammo is very much superior to British, American and Russian in terms of penetration when all rounds put on constant weight-diameter basis. We put the above analysis into book just to show how it supports the penetration figures we use, although there is quite a bit of other info. We have U.S. penetration data for German guns and ammo against American armor, and Russian 122mm APBC against U.S. armor. This allows us to directly compare German penetration data to American armor. More info next week when book is ready to ship. Table of contents available if you are interested. It is posted on the Yahoo tankers site, in the files section. Will provide address later. Almost forgot. Book shows how 75mm HE fired at low velocity is very superior to 88mm and 90mm HE fired at higher velocities against points on the ground. Book also compares British, U.S., German and Russian HE rounds for percentage of total weight as HE filler and makes all sorts of speculative and semi-substantiated guesstimates on what is better than what. And presents a detailed and totally challengeable analysis of HE ricochet fire characteristics, where 75mm HE reigns supreme (in my mind, at any rate). Along with page after page of slope effect curves, "how to" tables and curves on converting cast and high hardness armor to regular rolled stuff and firing test data analysis that proves stuff beyond the slightest shadow of a doubt, if you happen to be me. Others may wish to think about it some before they agree. Page after page of penetration data and armor stats, with armor type identified including "high probability of crap", otherwise known as flawed. And, as our piece de resistance, the world's greatest Tiger mantlet drawings (front and side), with armor thickness noted for each area and six pics from Saumur Museum that illustrate some of the finer points. And not to be outdone, hits on the Tiger mantlet free-edge are analyzes in thrilling detail (but not so much as to cause heart palpitations) that show how useless 76mm APCBC was against Tiger's mighty mantlet. More? Yes, lots more. Hard data, soft projectiles and armor, and all within a 200 page masterpiece. Enough reading for a lifetime (if you're a firefly). Always wanted to be a sideshow barker. How'd I do?

In previous threads I pointed out that CM underestimates some U.S. penetration figures and overestimates other, compared to TM9-1907. 37mm APCBC penetrates about 79mm of homogeneous armor at 25 yards (TM9-1907), which is a few millimeters short of the effective resistance of the Tiger rear hull. There is a small chance that 79mm penetration could get through the Tiger rear armor with enough energy to do something bad. There are also hits that strike the exhaust system parts on the rear hull and are lucky enough to continue on to the openings where the exhaust leaves the inside of the hull. Those fluke hits that occur when there are openings in armor and shots land on the openings. When the first Tigers were tested, 50mm AP penetrated the mantlet!!!!!!!! The hits landed at the bottom of unreinforced vision openings. Good reason to reinforce the mantlet after 140 mantlets were cranked out. Compare TM9-1907 for 37mm APCBC to CM, and then compare 500m data from TM9-1907 (81mm) to CM. 37mm APCBC rounds were tested by U.S. forces against the Panther side armor in France, it penetrated at the exact same range that was predicted by TM9-1907. And 40mm AP penetrated the Panther side at the same range that TM9-1907 predicts. When 75mm APCBC was tested against the Tiger 80mm armor, it penetrated at the same range and angle that TM9-1907 predicts.

Panther 75mm and PzKpfw IVH both fire a 15# projectile, Panther shell has more charge so it flies faster.

Face-hardened armor penetration by Russian ammo: We found some Kursk 1943 penetration range data from Russians giving range, gun and target armor with all angles, so we have a start. Currently looking at 45mm L46 against side and rear of Panther hull, where side is face-hardened and rear is homogeneous.

U.S. put out little ordnance reports for tankers and gun crews based on actual firing tests, as opposed to questionable calculations by some guys in an office in Detroit. 90mm HVAP against Tiger II was in a January 1945 report pamphlet, so tests must have been during the fall sometime. M36B1 was in action during November, which opens up the possibility of that vehicle having HVAP and using it during the test against Tiger II.

We found notes on 90 HVAP penetration of Tiger II glacis, nit sure if it is firing test or combat. 90mm gun aimed down at tank, which was in some sort of depression, so glacis angle less than 50° from vertical. Say armor angle is 47°. 150mm at 47° resists HVAP like 350mm at 0°. If armor quality is 0.90, than armor resistance drops to 315mm at 0°. Maybe Tiger II armor was 0.85 quality, or HVAP had more velocity than the average. TM9-1907 gives 90mm HVAP 314mm 0° penetration at point blank, so penetration of 150mm at 47° possible at very close range. Baily's Faint Praise book has something on this HVAP penetration of Tiger II by 90 gun. We started to collect firing test results about 20 years ago, and several boxes of my collection have disappeared every time we move. Can't find the 90 HVAP report, but scribbled notes suggest that Tiger II was in a depression or was lower than firing gun, or something like that.

We're looking for source of 90mm HVAP penetration of Tiger II front, which hopefully will be front hull glacis. The report we are searching for may also indicate if M36B1's have 90 HVAP, from what I remember Tiger II report was before Pershings made the scene. There are many little details that evolve into really long threads. We had one on U.S. 57mm anti-tank gun APDS some time ago on AFV News site. It appears that it was available and "probably" was used, even though it was not included in any official manuals or firing instructions or even ammo logs. Hunnicutt is usually a good source for HVAP availability dates, was 90mm HVAP around at same time as 90mm M36B1? That would suggest something, especially if Pershing was not in action at same time. Anyway, we're looking. I live in Albany, New York, and there is a real history of tanks, guns and ammo development in this area. Watervliet Arsenal, just north of Albany, built guns, a firm in Schenectady built tanks including the Grant and Lee (firm previously made locomotives), and some work on HVAP may have been completed in Schenectady. The Priest was also built in Schenectady, was a "secret weapon" that was designed to counter the "88". Priest built on Lee tank basis. Have read articles on the extreme precautions that were taken to hide the Priest from being disclosed. High walls were the rule to keep German spies from seeing anything. Some locals told me that there were several little sayings about the Lee during the war, none of which were positive. This was after Kasserine Pass. Lee armor was kind of thin if combat with Tigers, PzKpfw IVf2/G and 88 Flak guns was entered into. They have a 57mm anti-tank gun set up in the middle of Schenectady, and the Watervliet arsenal has a small but unusual assortment of guns, an odd looking anti-aircraft vehicle and what may be an M60 in the yard facing I-787. Watervliet built BIG naval guns with precision tools, and still builds gun barrels. Was HVAP developed by a Schenectady firm?

IS-2 is big compared to T34/85, which is the point the post was making. Tiger II against Pershing, face-to-face, is to compare frontal armor of Pershing against 88L71 gun. 88L71 and 128 are only guns to consistently penetrate Pershing front, regardless of hit location. There is a need to consider Tiger II against Pershing. HVAP is so fast and has such a flat trajectory that some gun sight drawbacks may be neutralized. There are stories of M18's hitting 3 tanks with 3 shots at 2000 yards, so gun sight deficiencies only show up some of the time. U.S. gun sights probably didn't have range lines for HVAP, but conversion factors were available. Eisenhower report has many cases where U.S. tanks bounce many shots off panzers at 2000m or longer range, problem is they bounced, not that they missed. [ 05-08-2001: Message edited by: rexford ]

The Russian Battlefield makes many statements about shortcomings of Russian ammo and equipment: poor armor on IS-2, and poor ammo for 45mm during '41-'42 period, and poor shells for 57mm anti-tank gun, and how 76.2mm field guns needed muzzle brakes cause carriage was not designed for that big a gun. It does not seem good to discount everything one reads on the basis of national bias. There are many reasonable and creditable things on The Russian Battlefield, including potentially poor armor on Tiger II. The way to deal with these things is to see if they make sense. We analyzed the firing tests against Tiger II presented in Jentz' books and The Russian Battlefield, and they show that the side armor was about equal to U.S. good armor. The Russians said Tiger II armor was inconsistent. I can live with that. U.S. 90mm guns penetrated the front hull of some Tiger II's that required poor armor.

The world's best rulebook, Advanced Squad Leader, also points out that Pershing helped to win battle for Remagen Bridge, but never crossed the bridge cause they were too heavy given the damage to structure. 310 Pershings in Europe at war's end, according to ASL. How many King Tigers were built, 486? How many made it to front? 200? The basic Advanced Squad Leader rulebook includes Russian and German vehicles, I purchased the vehicle and gun notes for British, Italians, Americans, etc. Has info on date of tank or gun introduction, unusual ammo introduction and relative availability, combat speed, crew survival, breakdown chances, relative turret speed, etc. Don't know if it is all available anymore for purchase. Little notes section for each tank and gun, includes mortars and rockets and other things. The Russian Battlefield has a very good article on captured King Tigers, the breakdown ridden drive to the testing grounds, and how the armor held up under attack by a variety of guns, including 88L71.

The 76mm HVAP round was the most accurate ammunition used during WW II, according to American and British gunners and analysis of the dispersion data. It combined a flat trajectory with little scatter about the flight path. I assume, but haven't seen any data, that 90mm HVAP would be similar in many respects. M36B1 with 90mm gun had HVAP late 1944, sources suggest that Pershings had ALOT of HVAP rounds, especially since there were only a few around for experimental purposes and why not spend on them. Several books state that M4A3E8 preferred in Korea due to ability of tank to move easily over terrain that would hinder Pershings. T34/85 good in Korea due to speed and nimble movement, IS-2m may have been in Korea but too big and slow, keeps bumping into things like KV-I (there are stories of KV-I tanks trying to cross bridges, but the tank kept driving into the sides until the tank broke a track). With regard to combat speed, my favorite source for all things large and small, the Advanced Squad Leader rulebook, gives M4A3E8 and Panther a 25% faster base speed than Pershing. Pershing is fast? The world's greatest wargame rulebook also states why M4A3E8 was preferred in Korea over Pershing:"Easy Eight" is "lighter and more agile.......preferred in that rugged countryside". Pershing gets the same base speed as Tiger E in Advanced Squad Leader, and Pershing is also slower than PzKpfw IVH. Advanced Squad Leader gives Pershing the standard breakdown chances, nothing unusual indicated. Pershing is a relatively slow, heavily armored U.S. tank with a big gun (for U.S.) and ALOT of vulnerable armor areas on front. When the Allies broke out in France, Cromwells worked well at getting places fast. But in the bocage, Cromwells were poor due to non-existent armor thickness. Pershing would have been good in bocage, poor during break-out phase. Was good during final stages and face-to-face confrontations. [ 05-08-2001: Message edited by: rexford ]

The 15% deficit of 2" cast when hit by 75mm rounds came from our group. 102mm cast performs a bit better when hit by 75mm rounds. We have ALOT of armor analysis reports for T34, KV-I, IS-2m, T34/85, etc., and Russian cast armor was one piece in all the analyse's by Brits and Americans. No sandwich plate combo's anywhere to be seen.

Pershing gun and armor analyzed using info in our upcoming book, effective armor resistance at 0°: Glacis, 102mm @ 46° 176mm resistance against 88 hits after slope effects and cast deficiency, can be penetrated by 88L71 to some impressive ranges. Will stop Panther hits at 300m due to 183mm armor resistance. Upper Glacis Center Area, 102mm @ 20° 105mm against 75mm hits after slope effects and cast deficiency, PzKpfw IVH penetrates to 1000m Nose, 76mm at 53° 167mm resistance against 75mm hits, Panther penetrates to 500m Mantlet, 114mm round (say 30° impact, which covers more than half the hits on mantlet) 143mm against 75mm hits, Panther penetrates to about 1000m, 88L71 penetrates to FAR OUT. If Pershing uses 90mm gun with 2800 fps muzzle velocity, this gun is about equal to Tiger 88L56 in terms of penetration and is inferior to Panther by quite a bit. HVAP is what makes 90mm a winner, and relatively thin Tiger E armor. Panther glacis, even brittle ones, will stop 90mm APCBC at any range (2800 fps muzzle velocity). HVAP is the key against Panther glacis. Face to face, Pershing may have slight advantage over Panther for as long as HVAP holds out. Pershing is better able to withstand wide angle hits on side armor than Panther, especially by pesky little guns. Is Pershing best tank of WW II? Face to face, Tiger II chews up Pershings, where only HVAP saves Pershing from total obliteration. Report given to Eisenhower says U.S. gun sights need bright light to work well, and German sights were superior during overcast conditions, which occurred alot during fall, winter and spring. Were Pershing sights superior to 75mm and 76mm armed tanks, the ones that don't work well during overcast conditions? Panther G has 2.5/5.0 gun sight magnification, what does Pershing have? 122mm APBC from IS-2m can penetrate Pershing front armor to very long range. Pershing is good but not great. 88L71 Pak would give Pershing a difficult time, and 88L56 Flak, given enough shots, could stop alot of Pershings by punching through the mantlet. Remember, German crews trained to aim at turret/hull line, which is where that 102mm at 20° front armor is.

Thanks for data sample. AP shot usually penetrates about 12% more than shell, Russian data shows giant difference. 70 vs 44. Data does not appear to differentiate between face-hardened and homogeneous armor penetration, PzKpfw III side armor is homogeneous, PzKpfw IV and V side is face-hardened. Maybe Russians didn' test against face-hardened armor, although some quoted figures for anti-tank rifle penetration state that it is against case hardened armor. Thanks for data.

In general, AP rounds without armor piercing caps penetrate less face-hardened armor than homogeneous. Armor piercing caps sit on the projectile shoulders with a little air space just above the nose, when the round hits face-hardened armor the impact is spread over the ammo shoulders instead of being concentrated on the nose. Since face-hardened armor defeats hits by shattering the nose before it digs in too far, anything that protects the nose is good. Ballistic windshield caps are too light, and too far from the projectile nose and shoulder, to do much. Anyway, Russian APBC does not have an armor piercing cap, but it does have a blunt nose which greatly increases the impact forces on the face-hardened layer (which is brittle). So we guess that Russian APBC penetrates about the same face-hardened as homogeneous, maybe more for 76.2 because blunt nose is higher percentage of total width. The Russian Battlefield site has a report on captured Panthers at Kursk with some penetration data. Info suggests that 76.2 penetrates more face-hardened than homogenous armor. That is all we know at this point. Not much. Since Eastern Front matches Russian APBC ammo against a horde of face-hardened armor carrying panzers (cept for a few like Tiger E), it becomes a guessing game. The most important front has the least accurate data.

What would be a good start would be penetration ranges against the front of some 1942 and 1943 panzers by a limited number of guns, say: 45mm and 76.2mm guns PzKpfw IIIH, IIIJ, IVF2/G and IVH. 1942 penetration ranges would cover IIIH and IIIJ and IVF2/G, 1943 would cover IVH and reinforced IVG. Would it be possible to have a small amount of data posted, since it may indicate whether homogeneous penetration data is acceptable against face-hardened, or requires adjustment. Thanks.

We have good data for Russian homogeneous penetration, but the book with penetration ranges sounds like a possible answer for face-hardened performance. If the curves are based on firing tests or combat reports, instead of some calculations made 500 miles from the front. Thanks for the lead.

"Rexford" is Lorrin Bird, and the rest of "we" is Robert Livingston. Numbered Collector Edition autographed copies will be reserved for those with the most responses to my posts, and a special suprise bonus for those who repeatedly posted similar messages. We expect to charge about $25 postpaid for the book, in U.S. funds. Thanks for nice comments.

April publishing date was missed due to some receipt of some really great info on Tiger mantlet, which allows us to annotate a drawing of the mantlet with the thicknesses, including the recessed areas for vision openings. We have access to German manual on Tiger mantlet. We also found a single equation that describes slope multipliers for all APCBC rounds (over 37mm) as a function of angle and T/D ratio. Another equation describes AP ammo. And a series of equations relates APBC blunt nose slope effects. Biggest problem is nothing on Russian APBC penetration of face-hardened armor, which hurts. PzKpfw III, IV, V and VIb carry face-hardened armor on no data for majority of Russian armor piercing rounds. Inquiries on numerous sites were not productive. Anyone live close enough to Kubinka to look in their records? Book will include armor specs for alot of tanks, designating cast, face-hardened, flawed and layered armor. Remember the Churchill thread some time back, how the armor around the MG on Churchill IV-VI was actually two 89mm plates on top of 13mm? Those Churchills can survive Panther hits at close range if the round lands on the thick, layered armor (has CM changed the Churchill nose armor yet to include the 20° angle, they show 0°). Turns out that layered armor may be more resistant than a single plate of same thickness if certain ratio's are met, and our book will present data on this. Book will also discuss validity of American penetration estimates for 75mm and 76mm APCBC when figures exceed TM9-1907, like CM. TM9-1907 has 90mm penetration for 75 APCBC at 0m, CM has 99mm at 100m. Makes a difference when Tigers are being hunted, due to 500m penetration of 80mm armor in TM requiring a perpendicular hit, CM allowing 500m penetration of 80mm at 20° lateral angle. Plus the book will go into shatter gap, where 76mm with 120mm penetration shatters on 102mm armor due to nose overstressing. We have prepared what we feel is the best single source on WW II armor resistance and projectile penetration. Oh, book will not include anti-tank rifles and bazooka/PIAT type weapons.