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Everything posted by ArgusEye

  1. Really great, thank you very much indeed!
  2. In making maps, I end up not using rocky terrain too much because it doesn't show up very clearly in game. Has anyone made a high-visibility version of the rocky terrains in CMAK?
  3. The S in S-mine is for 'Schnell' which means 'quick'. This referred to a large area of denial being covered by one mine, using the tripwires, or it being quickly converted to other detonating methods in the field without much additional equipment. According to a Dutch mine-lifters' manual from 1948, the rumour that the mine could be disarmed after you stepped on it was introduced deliberately by the British. The druckzünder had a three second delay (which would get longer as the mine deteriorated in the ground), so that a soldier would have stepped off the mine when it jumped. If a soldier could be convinced to stay on top of the device, he'd get blown to kingdom come, but the rest of the squad would stay safe. Since it didn't have to go through the rigours of being fired from a gun, its casing and filler could be designed for optimum fragmentation. Outside of its plane of maximum fragmentation, it was not very strong, but within it there was a lot of large shrapnel flying around. The mine-lifters' manual warns it has to be encapsulated equivalently to a 105mm artillery round.
  4. On re-reading I have to correct some items in my earlier post. It is misleading that I write that the 40(W) was 'only' named 40 because of the identical trajectory. It's slightly more complicated. The PzGr 40 was designed to penetrate armour slightly too thick for the PzGr 39. The 39 had superior damage potential, but the 40 could get through a bit more armour steel. Heer philosophy throughout the war was always to keep the guns powerful enough to allow the standard 39 model round to beat all but the most extreme protection, but that was not always practical. A subcaliber pfeilgeschoss with hard core was produced in some numbers to deal with the problem cases which invariably showed up as the war progressed. However, this subcaliber solution ran into several problems. First, the rounds were often used in cases where the 39 would be the better choice, but the gunner was intimidated by the target. Second, a whole secondary ammunition administration governed the distribution of special projectile ammunition, which made things needlessly complex, and still resulted in the rounds never being available where they were truly needed. Finally, the clincher: it used large amounts of Spanish tungsten, which was also needed for industrial tooling, and which got cut off by British threats to Spain in 1943. Whether or not these reasons were the right ones, the Krauts decided to kill the 40. First preliminarily, later permanently. During the interval that no new cores were made, the production of light metal outer shells continued. They had the tooling, so why not. When it was clear that these shells were never going to be used, they were stuck with a bajillion of them, and as the war progressed, a shortage of regular ammunition. The rest is easy to understand.
  5. When I was trying to find out whether the Russian 85mm was undermodeled in CMBB, I plodded through a lot of papers on AP ammunition. The most fruitful were the Gercke papers, since he was consulted in pretty much every ammunition development project in Germany. It's quite an interesting read. Do try to get the full set of papers, not just the part about armour plate proofing. There should be >500 pages. Most of which are tables and graphs. The Krauts made some impressive ammunition, especially in 88mm, but there were some spectacular failures as well. These projectiles seem to be of the latter category. Fritz in the field seemed to be confused easily by some pfeilgeschosse being superior, and others far inferior to the regular round, even though the differences were clearly marked.
  6. PzGr 40 was the high-performance flat-trajectory subcaliber round. PzGr 40(W) was only named the same because it was designed to follow the same trajectory and use the same sighting, but it was designed against softer targets. Not because it could do anything the 39 or 40 couldn't do, but because it was a cheap alternative that could be made without expensive alloying. It was meant for shooting up light tanks, armored cars or light bunkers. PzGr 40(S) was the same as the (W), but with a better alloy because the (W) turned out to suck too hard. Neither of the newer rounds was very successful, apparently. They never made it to the front in large numbers.
  7. How can you tell? Those might easily be 5" and 3" naval dual purpose guns firing. I have seen 40mm Bofors fuse setting equipment, but never older than the 60s. Do you have any background information?
  8. The same target is struck by obvious pistol projectiles. There is even some footage of the pistol muzzle in the movie. And let's face it, there is no displacement or damage evident in the target material. To top it off, the splayed projectile slides across the surface of the target. Would it do that if it were anchored to a surface deformation due to a penetrating core? I find it very hard to see as anything else than a long pistol projectile.
  9. Do you disagree that the pointy-tailed projectile in the first impacts is the same as the one disintegrating at 7:50? We do see fluid plasticity in the first few impacts, but this is due to the soft metal target, not to hyperplasticity. And normal plasticity, as here, is indeed the main failure mode of Sherman armour.
  10. At 07:50 you see the same projectile hitting some actual steel. It splays open, showing it to be a simple full metal jacket bullet. I don't think we see any aluminium used as a target. It sparks, spalls like crazy, and doesn't take much elastic or ductile strain before it cracks, and I didn't see any of that here. From 3:15 we see something that might well be aluminium. Hyperplasticity happens if the impact is fast enough to cause dispersion of the compression waves generated by the collision in the target material to keep ductile [plastic] deformation modes for greater strains than can be achieved in quasistatic deformations. The exact mechanisms are still being studied, but the dispersion of the medium are clearly the key. Since these are momentum deformations rather than hydrostatic deformations, the Poisson effect does not contribute to changing the yield mode of the material and this allows for ductile, even fluid plasticity to occur much longer. In WWII this is mostly seen for shaped charges, as very few other projectiles and armour types even came close to this type of velocities. I am very confident we don't see any hyperplasticity here.
  11. It's an interesting discussion, without the baseless assertions that mar most of these threads. Good read. I must disagree on the high-speed movies showing hyperplasticity though. There is no sign of it, all we see is small arms projectiles hitting objects. I think you refer to the bullets hitting the lead sheet, which shows the fluid looking cratering we see on tanks with soft armour. Hyperplasticity is a different phenomenon entirely.
  12. A complex issue. Let me set out what I consider a valid comparison here: There are many ways to count the amount of manpower needed for production of an item like a tank. The RWM had the annoying tendency to count not just assembly and manufacture time for the parts, but also the man hours put into collecting the ore and coal, manufacture of the raw materials, transport, design, and so forth. Some comparisons include the spare parts made per tank, some don't. There is something to say for this on a large scale comparison, but when it boils down to getting treads in the mud, what matters is how many tanks of each type you can get out of a given factory. In tank production in Germany, the bottlenecks were two: the production lines and the strategic materials. Much is made in books of the lack of automated assembly lines for the German tanks, as if this was the bottleneck of tank production. However, the main issue according to the RWM papers was in the cutting and welding of the armored components. Assembly was only as quick as these components could be delivered, and could therefore be done on small scale. The IV had a nasty design to cut and bend, whereas the Panther was designed from the start to be an easy model to do this to. [They may have over-economized on the welding, given the cracking problems in the field!] On this bottleneck, the Panther, despite its greater weight, was easier to speed up. Go look at the amount of holes to drill in the Panzerwanne of each type. Look how many holes are neatly round in each type. With its greater weight, the Panther required more man-hours in materials, but it went through the tank factory quicker. Look how quickly its production ramps up when compared to long-established and experience-optimized IV production lines. Factory man hours of the Panther are listed at 2000 by MAN, whereas Daimler Benz quotes 5000 production line man hours for the IV. Of course I cannot be sure that they use exactly the same definitions, but it seems alltogether plausible. The Panther could, by design, be farmed out much more effectively. As to the requirements of strategic materials, that can be looked up unambiguously. Some favour the IV, like aluminium, some favour the Panther, like rubber. All in all, the IV doesn't come out ahead here. There is no way for me to know how these bottlenecks might have moved if the Panther had supplanted the IV. Materials used for the IV would have become available for the Panther, but there might -for instance- have been new troubles, like insufficient spares and consumables for the modern welding machines for the Panther, greater consumption of high thickness armour plate, and so forth. I'd love to tell you which RWM papers were involved, but I stupidly haven't written it down. I therefore have very little to back my story up, sorry. Comparing by monetary cost may be the best way to look at it, because it is the way economics works, after all. On the other hand, this is not really a free-market situation. So maybe not. As to the German army being starved of IV's for half a year: it would have been dire indeed. But being equipped with IV's when you could have been running Panthers is dire as well. OKH saw it was on a path to damnation and wanted to gamble. Speer didn't.
  13. I must disagree about the Speer issue. Speer indeed came across the plan to kill the IV in favour of the V, and together with Hitler and Guderian put a stop to it. The argument was not that the Panther was more labour intensive, because it was not. A IV took more man hours and more strategic materials [outside of armour alloying materials] than a Panther. In fact, in the long run this turned out to be the wrong decision. The IV was reviled by its crews and the maintenance corps in the late years of the war, whereas the Panther was the tank that could have made a real difference in sufficient numbers. The III was not made as tanks anymore, but was the mainstay of the mobile infantry support forces in the guise of the StuG III. A strong lobby by the officers of infantry divisions had almost gotten IV production switched over completely to StuG IV if Guderian hadn't intervened. The only reason Speer could even decide this change was that the Panther hadn't matured enough yet. Otherwise the change-over would have been initiated earlier. The real reason was that canceling the IV whilst setting up the factories for the V would have made a gap in tank production. The Heer considered being stuck without fresh tanks for a half a year, making do with assault guns, but being rewarded with a deluge of Panthers after these lean months preferable to plodding around with IV's and a trickle of Panthers. Speer disagreed, as did Hitler, because they didn't want to lose momentum. The OKH didn't consider itself having much momentum to keep.
  14. I haven't been able to find the original papers, but WaPrüf seems to have written a specification in late '42 for industry to find a way to lower repair demands placed upon field units regarding small damages due to low power anti-tank weapons such as ATR's. The tanks were considered well-armoured enough to withstand the ATR fire, and weren't likely to be killed by it, but damage occurred nonetheless. This damage overloaded frontline welding crews. HASAG came up with a proposal for a mesh to destabilize hard-cored projectiles. The hard pointy projectile would gouge a lot less metal if it had been disturbed on its trajectory. This got tested in february of '43 at the plant. Both the mesh design and a competing armour plate design defeated the ATR so that its damage was lowered below repair requirements. It's unclear why the mesh was much less popular, and the armour plate was chosen, because the mesh would be lighter. Also shrapnel damage was tested against, and the Schürzen solution found acceptable. As to shaped charges, the Germans didn't design the Schürzen for this purpose, but they did test whether it worked against them in december '44. The Schürzen once again showed sterling service against ATR's, but gave zero extra protection against Panzerfaust, Ofenrohr or even the Bazooka. In fact there is suggestion that whilst bazooka projectiles often failed to produce penetration when hitting a projection, like handles, bolts, track links, or whatever, the smooth Schürzen helped them not to be duds. As to Zimmerit, it was introduced only after several thousand German magnetic charges fell into Soviet hands. Since the Germans considered this weapon greatly superior to anything the Soviets had been using, they were very concerned it would be used against them, and even more concerned the Soviets would start copying them. That's where Zimmerit came in. When it was clear that Ivan didn't even try them out, the manufacturers considered leaving the stuff off, but the frontline troops didn't want to be 'less protected' and it was continued for morale purposes.
  15. Digging up weapons, great. Diggin up personal items discarded in the field, fine. Being excited about finding landmines, not my idea of fun, but go for it. It's the corpse robbing I object to.
  16. So the dispute reduces to 'side with me on technical issues or you're a Nazi!'.
  17. Excuse me, I'm sorry if I missed you posting this earlier. You came with much interesting stuff to view, I must have accidentally skipped it.
  18. Short answer: after the power problem is solved, other problems become dominant, none of which get solved by interleaving wheels. The smoothness of the ride is quite sufficient for human comfort, with hydraulic stabilization allowing firing on the move. Wide wheels roll on wide tracks. The track resistance is higher, but what limits the speed and maneuverability now is not the flatness of the track, but mainly its inertia. Interleaving would only fix problems that don't matter anymore.
  19. JonS, be happy with that weight, it keeps the boom inside. A nice find here [0:07 to 0:14]: Off the cuff, that is a PzF II being fired. Observe how the soldier points the rear of the tube at the inner wall of his Schützenloch, yet he doesn't suffer any harm.
  20. Thank you, John! I'll dig into it, as soon as I can get my hands on my collection. I should have that book somewhere. He is generally a good source, not quite primary, but close. I'll get back to this topic asap. I'm babysitting a machine at work at the moment.
  21. Womble, I tried giving a direct blow-by-blow answer, but it became unreadable. Let me lecture a bit about 'venturis'. When firing a rcl, one suddenly generates a lot of gas inside a piece of pipe that has a projectile stuck in one end. The gas expands, and pushes the projectile out. How well it achieves this is dependent in equal measure upon the pressure attained by the gas, and how long it maintains this pressure. You will appreciate that with one end of the pipe open, a lot of gas will just escape. This drops the pressure, as gas escapes during generation, and shortens pressure duration, since the gas keeps escaping during and after generation. The easier the escape down the back of the tube is, the more energy is lost, therefore the lower the energy efficiency of the shot. The way to get the most out of our shot is to completely close the rear of the weapon. This causes it to become a gun. Highly efficient, but it has a strong recoil, and it needs to withstand the high pressures that typify guns. Two things we were trying to avoid. There we turn to a venturi system. Stripped of all mysticism, what is commonly called a venturi is nothing more than a stricture in the gas flow followed by a reclaiming expansion. The stricture is what increases pressure and pressure duration, because it inhibits gas escape. The reclaiming expansion is what gives some extra forward momentum back to the launcher to compensate the backward momentum imparted on it by the gas acting on the stricture. The clever bit is that the extra energy used for the shot comes from the reclaiming expansion robbing the exiting expanding gas. This is how a venturi exit increases efficiency. You get higher velocities with less propellant. The price you pay for this additional efficiency is higher launcher weight and strength. The burn chamber and projectile run must be able to withstand the launch pressures, and the expansion cone on the rear is not a light-weight toy either. The more complex gas system is also more prone to trouble. If your cone gets loose, or your stricture fouls up, suddenly your launcher gets very lively and doesn't merit the name 'recoilless' anymore. Or blows up, as some RPG7s seem to do when in the hands of idiots. Frugal idiot uses damaged strip charge, fouls the stricture, and the ejector of the second shot goes high-order next to his ear. When we are aiming for efficiency, we might as well not stop at the venturi. We might, for instance, compute or test how long the obturation of the projectile lasts, and make sure that we spend all our propulsion on it before that time. A big fiery blast from the front of our rcl isn't going to do anyone any good. A well tuned rcl doesn't have a lot of muzzle flame. If three quarters of your propellant gets wasted out the muzzle, you're doing something very wrong indeed. In any rcl, the bulk goes back, as it should. Pictured here is the Carl Gustav, an older RCL [although it does have venturi'd exhaust], but modernized time and time again, and fired with modern, well-tuned ammunition. No matter how much propellant you burn, it has to go somewhere. No matter through how many venturis, baffles, dispersers or muzzle brakes it goes, it doesn't disappear into nowhere. The overpressure is therefore not diminished in any significant way. Not that it matters, because you'll have to fire from inside a fridge to get killed by overpressure, and you'll need to fire from a walk-in closet to get suppressed. I can therefore say with confidence that the shockwaves -however insignificant to the damage they may be- are not influenced by venturis. Shockwaves are entirely momentum-based, and that has to be compensated anyway. Overpressure is also solely dependant upon the amount of gas generated, id est the amount of propellant, without consideration of any venturi. Even the heat of combustion still is contained in the gas, which exits in bulk from the rear of the launcher.. The expansion cone will rob some heat from the gas, but this is also lost to non-utilized expansion in a straight exit. The venturi will cause big malfunctions if used with crude propellants like black powder, but this is again not a great improvement due to the venturi, but a forced choice. The only thing that the venturi system will do, is cause the focused ablative exhaust stream to be much reduced. The expansion will dissipate it much quicker. In this way, it does make the weapon a lot safer.
  22. Thank you John Kettler, but what I'm actually looking for is the information that these people base the story on. I don't find in lessons learned documents that the Krauts were especially disappointed in the interleaved tanks. Everything in the inventory clogged and froze, interleaved or not. I conclude that either the interleaved suspensions are unduly singled out, or that I haven't found the pertinent documents yet. I was hoping someone would grog me the appropriate documents. Thus far I read several complaints about the Pz IV, but since it was the popular thing to hate in the Panzer corps, that might be unfair too. MikeyD, if the Ferdinand is a red herring, then what is a closer comparison to a non-interleaved tank of similar proportions? It is rather glib to just dismiss it. The spring system, the hybrid drive, the fuel type - these things do not explain why it wouldn't turn, and bogged easily. The track loading does. To call the E-series pies-in-the-sky designs is a bit optimistic. What little actual documentation survived does not show any technical choices being made beyond basic capability desires.
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