Three types of PzGr 40 (only one modeled)

[John Kettler]

This was quite the shock when I encountered it. In CMBN and CMFI, there is the PzGr 40 (Hartkern = tungsten carbide core), but as the thread shows, there was an Ersatz projectile, the PzGr 40 (W) Weicheisen (soft iron) too, which I'd never had so much as a whiff regarding. It has a soft iron core, instead of the scarce tungsten carbide. Penetration performance delta's enormous.

http://www.wk2ammo.com/showthread.php?2377-7-5cm-PzGr-40-amp-PzGr-40-W-fur-KwK-40

Firing tests conducted by the Germans.

http://fhpubforum.warumdarum.de/index.php?topic=5347.305;wap2

Oops! There's apparently a second version of the Ersatz PzGr 40 called PzGr 40 (St), which has to be Stahl or steel.

http://translate.google.com/translate?hl=en&sl=ru&u=http://www.vif2ne.ru/nvk/forum/arhprint/2323748&prev=/search%3Fq%3Dpzgr%2B40%2B(W)%26client%3Dsafari%26rls%3Den

This is confirmed by our very own Claus B (ordnance grog extraordinaire) here. Quite the grog discussion ensues. Particularly interesting is the discussion of the whys of manufacturing and employing ammo which performed worse than PzGr 39.

http://forum.axishistory.com/viewtopic.php?f=47&t=99591

Recapping, there were PzGr 40 (tungsten carbide core), PzGr 40 (W), with a soft iron core and PzGr 40 (St), with a presumably hardened steel core.

Regards,

John Kettler

[ArgusEye]

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.

[John Kettler]

ArgusEye,

News to me. Where, pray tell, did you come up with your information? I read what I found and don't recall seeing what you so forthrightly described.

Regards,

John Kettler

[Bulletpoint]

I guess the reason it failed was because, when you are in your tank, you want to have a round chambered in case you suddenly need it. Then, which round do you choose, the expensive but powerful one or the cheap shot?

If you choose the soft round, you might save the Reich a few coins in metals, in case an armoured car appears, but you might lose your life instead, if you're suddenly faced with an enemy tank. Not a good value proposition.

[ArgusEye]

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.

[Michael Emrys]

I guess the reason it failed was because, when you are in your tank, you want to have a round chambered in case you suddenly need it. Then, which round do you choose, the expensive but powerful one or the cheap shot?

If you choose the soft round, you might save the Reich a few coins in metals, in case an armoured car appears, but you might lose your life instead, if you're suddenly faced with an enemy tank. Not a good value proposition.

This is the reverse of what I've been hearing for years. Since the really good stuff was usually rare and hard to come by, you didn't want to waste one and not have it when you needed it. So you would fire one of the more common rounds until a burst on target showed that you had the range right, and then load one of the harder hitters if it seemed that the cheap stuff was not doing the job.

Also, unless the crew was explicitly expecting to encounter armor, they would usually have HE up the spout since in general there were many more soft than hard targets on the battlefield, and many of those can cause you grief as well. If a hard target was spotted, the fastest way to unload the HE was to fire it. Even against armor, that can rattle the enemy crew and give you time to load the AP.

Michael

[ArgusEye]

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.

[Michael Emrys]

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.

Yet more reasons why Germany should never have gone to war in the first place.

Michael