The DesertFox Posted October 3, 2000 Share Posted October 3, 2000 Markus, Only 2 short remarks [i´m still digging through my bookshelf ] However, why I asked for FLAK 41L74 data: Hogg states that the FLAK 41L74 projectile was 100% identical with the FLAK 18/36 L56 projectile. They only changed the cartridge cases which makes sense if you want to reach the "Aussenballistik of a 12,8cm FLAK", furthermore as we all know the FLAK 41 was totally different gundesign. Interesting sideremark, the SpGrPatr, which was fired from the 88L/71 was 100% identical with the SpGrPatr of the 88L/74. Now the interesting part: I have a penetration-valueset here, out of Piekalkiewicz "Die 8,8 Flak im Erdkampfeinsatz" which is within a few milimetres of the 88L71 and we have Hogg who says about the PzGr 39/1 Flak 41 "....giving a muzzle velocity of 980mps(3215fps) and a claimed penetration of 202mm at 1000m at 3° (7,95in at 1095yd)." Now this would mean that it is absolutely no problem to reach the ballistics of the 88L71 with a 9,5kg projectile. I guess it´s more a question of the amount and quality of propelling charge, and as I dug out so far, the amount of propelling charge was 2,52kg for the 88L56 (Digl R P) and 5,12kg (Gudol R P) for the 88L74 and 6,83kg (Gudol R P) for the 88L71. Of course this is only my totally privat conjecture Cheers Helge ------------------ Sbelling chequed wyth MICROSOFT SPELLCHECKER - vorgs grate! - The DesertFox - Email: desertfox1891@hotmail.com WWW: http://www.geocities.com/desertfox1891 Link to comment Share on other sites More sharing options...
Paul Lakowski Posted October 3, 2000 Share Posted October 3, 2000 Helge & company in Ivan Hoggs 'German Arty of WW-II', he states on the topic of AP ammo design.... German practice in this field was more-or-less in line with the rest of the world,though there were one or two interesting oddities. The shell material was originally a nickel-chromiun- molybdenum steel , but as this quality became scarce a silicon-manganese chromium type took its place. This could be hardened satisfactorily (so that penetrative performance was the same ) but the alloy was more brittle and tended to shatter more easily , thus failing to carry through into the target." Now this may not sould like it matters but it may as ballistics has shown that in cases of thick penetration the whole rod length effects penetration so if the defeat of the rear section of the plate is dependant on the projectile design this will be less if the rod shatters.Hogg goes on to say ... In 1943 a design of shell was introduced that had an alloy tip flash butt-welded to a plain carbon-steel body . This economised on alloy steel and also had a interesting by product: when striking at an angle , the tip often broke off cleanly across the weld to leave a flat head shot which , in some types of angle attack , could be advantageous." Again this may not sound like much but its well known that blunt rods penetrate slanted armor much better than sharp rods due to the fact that the turning forces on the sharp rod are not present on the blunt ones. John I'll put this [and Helges pic]to Robert and ask his opinion . Link to comment Share on other sites More sharing options...
M Hofbauer Posted October 3, 2000 Share Posted October 3, 2000 well, seems you got me on the FlaK 41 projectile, then. it was just a WAG opinion, and I am more than willing to accept if they were the same ammo. Now this would mean that it is absolutely no problem to reach the ballistics of the 88L71 with a 9,5kg projectile. ahh, but that is assuming that the data was indeed for a 9.5kg projectile! (petitio principii?) I guess it´s more a question of the amount and quality of propelling charge, and as I dug out so far, the amount of propelling charge was 2,52kg for the 88L56 (Digl R P) and 5,12kg (Gudol R P) for the 88L74 and 6,83kg (Gudol R P) for the 88L71. Helge (insomniac, eh?), I'm not an engineer, but it seems there is nothing in the propellant data / features relevant to AP that isn't already included in projectile Vo / Eo (Vo and Eo being a result of all the propellant effects). IOW, it doesn't mater to AP performance whether the Eo / Vo is attained by the use of Gudol, Diglykol, nitrocellulose, blackpowder or springforce doesn't matter it seems to me. ------------------ "Say i think u all need to chill out." (GAZ_NZ) Link to comment Share on other sites More sharing options...
The DesertFox Posted October 3, 2000 Share Posted October 3, 2000 <BLOCKQUOTE>quote:</font><HR>ahh, but that is assuming that the data was indeed for a 9.5kg projectile! (petitio principii?)<HR></BLOCKQUOTE> Sure, pure guesswork and nothing more do I say. <G> Same applies of course to the propellant charge stuff. However, as it seems to me, it was possible to optain the same (nearly) penetration with a lighter projectile fired with a lower muzzle velocity. Now how can you compensate the shorter barrel and heavier projectile of the 88L71? With a higher amount of propellant charge ? Or am I off the mark here ? Cheers Helge ------------------ Sbelling chequed wyth MICROSOFT SPELLCHECKER - vorgs grate! - The DesertFox - Email: desertfox1891@hotmail.com WWW: http://www.geocities.com/desertfox1891 Link to comment Share on other sites More sharing options...
Berkut Posted October 3, 2000 Share Posted October 3, 2000 Markus You are quite right I did quote the ammunition statistics for the PzGr40/43. But that is a completely different type of projectile from the PzGr40. The PzGr40 employed a tungsten carbide core, and was employed in combat, but was withdrawn due to shortages of the ore in 1943. The PzGr40/43, I believe, is an AP shell rather than AP shot. My comment regarding the Tigers main gun employing the same ammunition as the pak 43/1 and 40/41 forgot to mention that the projectiles, not the cartridge cases, were the same as those employed by the Flak41. A different cartridge case would give a completely different weight. As for the increased penetration of these shells. It is not only affected by the length of the barrel, but the fact that the germans would have had to rely more on the use of AP shells, rather than conventional AP solid shot. The AP shell, like the AP shot has an inner core with a hardened tip, but the rear is bored out and filled with explosive and sealed off with a base fuse. When shell hits, you get penetration (hopefully) of the armour by the hardened tip, the fuse initiates due to the shock of deacceleration and finally detonation occurs as it passes through the plate. Or thats the theory according to Mr Hogg. The reason that i have brought this up, is when reading the previous posts I thought that maybe some of us had forgotten that there was a difference. Or have I been stating the obvious? ------------------ BERKUT <BLOCKQUOTE>quote:</font><HR>As always feel free to query, deride, or just nod knowingly<HR></BLOCKQUOTE> Link to comment Share on other sites More sharing options...
M Hofbauer Posted October 3, 2000 Share Posted October 3, 2000 Berkut, if you mean that the FlaK 41 used the same ammo ok then it makes sense, and you are probably right too, as Helge pointed out in the meantime, too, and the Handbook on GMF (and therewith my guess too) is probably wrong. in what little humble opinion I have on this matter (I am not exactly a tankie expert) I beg to disagree however on the rest of your post: The PzGr40 employed a tungsten carbide core, and was employed in combat, but was withdrawn due to shortages of the ore in 1943. The PzGr40/43, I believe, is an AP shell rather than AP shot. 8,8cm Pzgr. 40/43 simply means it is the 8,8cm tungsten core round (Pzgr.40 type) for the PaK 43, it has a tungsten core with no explosive charge (not even the small one sometimes found in AP shells as you described correctly) (as a rough rule of thumb, for all calibers I found that usually Panzergranate (or Panzersprenggranate) 39 is the regular AP ammo, often of the type you describe (hence Panzersprenggranate), while the Panzergranate 40 is the tungsten version). IOW, there never was a "8,8cm Pzgr.40" for the KwK 43 / PaK 43, since "Pzgr. 40" alone is not specific, it simply refers to a type (Wolfram-Hartkerngeschoss tungsten core), and the designation "8,8cm Pzgr.40" was already occupied by the 8,8cm ammo for the KwK 36 (88L56). Hence the modified designation "8,8cm Pzgr. 40/43". You might confuse this with the 12,8cm Pzgr. 43 which was the AP ammo for the PaK 44 and indeed was an AP shell of the construction type you descibe, with a small explovise charge within the AP projectile. Come to think of it, I don't recall ever seeing a tungsten round (Pzgr.40) with such a small explosive filler added, wouldn't make sense, would it? Besides, even the projectiles that did use it I am not sure and rather sceptical of their effectiveness. Common reason would dictate that a projectile which has to penetrate armor and is subject to extreme stresses during the procedure should have more success by being a solid shot with more weight rather than being made fragile by being hollow and filled with a bit of explosive. That diminutive explosive filler might make sense when a full or as good as full penetration is achieved to increase the effect, but I doubt it helps a lot with the penetration in the first place, rather the contrary (when compared with the alternative that this filler instead would be taken up by solid AP projectile core mass) - just MHO, of course. yours sincerely, M.Hofbauer ------------------ "Say i think u all need to chill out." (GAZ_NZ) [edited for number typos which are a rather serious problem given the designations etc. vital to the issue] [This message has been edited by M Hofbauer (edited 10-03-2000).] Link to comment Share on other sites More sharing options...
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