Bismarck a dud shells?

[Karl Heidenreich]

One issue that always contaminated discussions regarding Bismarck is the fact that some shells fired against PoW didn´t detonate as they were duds.
In popular believing now there is a consensus that Bismarck was:
1. A mishitter because she didn´t hit anything at her final battle on May 27th.
2. That German shells were of poor quality when compared with other navies´shells.

The question is if that perception of the German shells was true, or was that a problem with all the shells of all the navies at the early years of WWII?

Best regards.

P.S. I do not refer to the miss hitter remark because it was demostrated long ago in other thread that she was not that.

[tommy303]

On the whole German naval shells appear to have been about average in reliability--i.e., the incidence of duds does not seem any worse than that experienced in other navies. That said, there were some issues with German shells in that the rate of low order detonations was fairly high in their SAP and AP naval projectiles. This is attributable to two factors: first the Germans employed relatively small gaines to initiate detonation of the shell filler.

The purpose of the gaine is to convert the flame produced by the fuze detonator and magazine into a detonation wave which will initiate the high explosive filler of the shell and in most German shells this was TNT. In WW1 the process was to use a container of picric acid crystals which could be initiated by flame from the fuze and detonate of its own accord, thus providing the TNT filler with the required detonation wave. However, it was found that picric acid was unreliable in that respect, resulting in many instances of shells going off with low order detonations--not getting the most blast and splinter effect possible.

Following WW1 new fuzes and gaines were developed for the Navy and improved the rate of detonation. The new gaines used, again, picric acid as the main explosive, but also incorporated lead azide as an initiator and a small tetryl capsule to insure detonation of the picric acid. During the course of the war, the gaine explosive was gradually changed from picric acid to heavily densensitized PETN.

However, low order detonations continued to occur from time to time, simply because the gaines were too small--or perhaps only marginally large enough to detonate the desensitized TNT filler of AP and SAP shells. The reasoning appears to have been the desire to limit the amount of sensitive explosives in the gaines of piercing type shells in order to minimize the possibility of premature concussive detonations. Nose fuzed HE shells had much larger gaines and more tetryl booster capsules.

When compared to other countries naval shells, the German ones are by no means deffective, at least in terms of reliability. It would seem that testing of fuzes by various countries was not always done in a realistic manner or at least not comprehensively. It is interesting to note that both the USN and RN changed their gaine explosives at about the same time as the Germans--ie after the war started and some experience had been gained in the process.

[Karl Heidenreich]

Thanks tommy.

[RF]

There are plenty of Kriegsmarine surface ship actions where there certainly was no evidence of dud shells - certainly Thor had no such problem with the three AMC's she engaged, or Kormoran with Sydney.

It could be these ''dud'' shells didn't detonate because they only scored glancing and not direct hits.
The shell that blew up Hood was certainly no dud.

One of POW's hits was a shell below the waterline that didn't explode.

[tommy303]

Hi RF,

For the most part, the auxiliary cruisers would have used mostly nose fuzed HE, and these generally worked quite well. The main problem was in the base fuzed shells, and it was not just the Germans that had troubles with AP and SAP. When one considers how an AP shell and fuze system operate, it is amazing they work at all. The fuze has to be robust so it survives the shock of a shell slamming into armour, it must be simple enough in principle to operate at various angles of impact; have safety devices to make it safe to transport and fire from a gun, yet still arm itself reliably on firing; a built in delay to allow it time to penetrate through armour; sufficiently powerful explosives in the detonation train to set off the very insensitive main filler of the shell, yet not so sensitive as to go off from impact. All things considered, the criteria were so difficult for piercing shells that a higher proportion of failures were almost to be expected and to a degree tolerated.

[RF]

Hi RF,

For the most part, the auxiliary cruisers would have used mostly nose fuzed HE

I think Kormoran did have some AP shells that were used on Sydney.