Bouncing Bazooka's

About two months ago I mentioned, on my Facebook page, a friend in the US by the name of Harold Biondo. Now he's a lucky bloke, and gets to spend his time leafing through the US Archives. He recently came up trumps again, finding this testing report:

At first glance It's pretty earth-shattering stuff. Tanks with Zimmerit on them are proof against Bazooka's and presumably other early shaped charge warheads like the PIAT! Simply by providing a cushioning effect against the fuse. However, this report provides an ideal example for you historians on critical thought, and how to deal with sources. Now, I have no doubt that some of the doggy denizens of the internet who have vested interests will try to make much of the claims held within the above letter, I saw enough of that with the Japanese heavy tanks from my first book, but it’s something we'll have to bear as long as there's free access to the internet.

First, let’s review what we do know about Zimmerit. Zimmerit was born out of a problem that was facing all nations. Technology was advancing fast enough that tank armour was pretty quickly leaving infantry anti-tank weapons behind. After the opening salvos of the war it became pretty clear that anti-tank rifles were not going to do the job any more, so everyone started scrambling for ways to defeat the armour. For example, Britain produced the No 68 anti-tank grenade which could be fired from a cup discharger from a normal service rifle. This was a pretty poor warhead but did have the advantage of starting research that would eventually culminate in the PIAT, but that is a story for another time (and is going into a book!). In the meantime, Britain used the sticky bomb, a kind of hand thrown HESH round which you could use to beat a tank to death with.

Note the guy on the right? He's about to smash his sticky bomb onto the hull of this Valentine "Panzer", at which point the sticky glue will hold the bomb in place and allow the explosive gel to spread. At the same time, when the safety lever is released it starts a short time fuse before detonating.

In Germany thoughts turned to HEAT weapons as well and resulted in the Hafthohlladung. Unlike the sticky bomb, which used glue to affix itself, the Hafthohlladung used strong magnets. Now weapon development in Germany during the war was one of trying to stay one step ahead of everyone. You can clearly see it when you look at tanks. Each generation of AFV's would be one up on the previous generation as Germany tried to introduce the answer to their own tank design. This ensured that if any of the Allies tried to match them, they would be ahead and have better tanks. Of course, this all went horribly wrong when the Allies reached the level of the Sherman and happily stayed there, while the Germans kept on devoting massive amounts of time and energy to getting the newest thing.

As they kept designing the counter to their own weapons, the obvious concern was the magnetic anti-tank mine. This is where Zimmerit arrived. It was a paste designed to be added to the tank that would cause any magnetic mines to fall off. When applied it could be allowed to dry naturally, but this would take eight days. By using a blow torch this could be sped up to two days to coat a tank. The use of a torch started considerable fires as the solvents used in the application were burnt off, but the time saved was considered worth it. Earlier I mentioned that Germany spent a lot of time and effort preparing for an enemy weapon that was not yet in the field, and here is a prime example. In the ten or so months that Zimmerit was applied to German tanks roughly 15,000 tanks and AFV's were produced. Please do note this is a very rough figure to illustrate the point. At two days per tank that equates to 82 years worth of work just to apply the Zimmerit!

Zimmerit was discontinued from September 1944, which leads us back to the original report quite nicely. You'll note that Captain John Long states that tanks equipped with this covering were only encountered in Belgium. Most of Belgium was captured in September to November 1944, which seems to tie up quite nicely with Zimmerit service. But there are additional problems with his account, which illustrate why eyewitness reports are so notoriously difficult.

Tiger turret nicely showing off the Zimmerit, as some areas have been knocked off.

First, he states the colour as green-grey (possibly German field grey?), but 15% of the composition of Zimmerit is pigment, which gives it an ochre colour. Next he states that the thickness of the covering was 6.35-19.05mm. Yet every other source I can find states that the Zimmerit layer was between 4-6mm. It could be Cpt Long misremembering the facts, as this report seems to have been generated sometime after February 1945. Or it can be explained away, by such factors as painting the tank and dodgy measurement taking.

That last point applies in spades to the rest of the report. Those of you who have seen reports from grown ups at dedicated trials departments will know that every aspect of the trial is documented. Often batch lots of ammo are recorded. Indeed, in testing one form of protection, one trials department had to source ammunition from a particular batch, from a particular factory, that had gone out of production the year before just to ensure consistency in the trials. This involved the British logistics system scouring its depots for boxes of ammo that had not been yet fired off (You'll be glad to hear, that it was successful, the testing proved the facts, and the Germans got a hell of a surprise when they found themselves on the wrong end of a WASP flamethrower and couldn't kill it).

So here we are to ask so many questions of Cpt Longs trials. What was the fusing like, the angle of impact, what type of warhead and rocket (the M6 Bazooka rocket was notoriously unreliable)? Also, what was the expected result? This last point should be considered as the text talks about rockets not sticking in the covering... was this something you were expecting? Why? We don't even know the number of rockets fired. There are just too many variables not recorded in this report, so we cannot say why Cpt Long got the results he did.

What we do know is that HEAT warheads were killing German tanks with Zimmerit, and that the Germans stopped applying it from September 1944. if it was so effective at stopping incoming HEAT warheads you can bet the Germans would have been plastering it all over their tanks, yet they did not. This would indicate the problem was with Cpt Long's methodology. This is why you should always be careful of badly documented reports of trials carried out by troops in the field!

Still a damn interesting find by Harold, so our thanks to him for letting me share it with you.