Fuses

[RogerKP]

Here we have two German alloy fuses.The one on the left is from a 151/20mm and is marked AZ 1528A , the other is from a 20mm FF, which has no markings at all, but blue paint matching the blue of the incendiary round. These fuses are hollow and have closed tops and seem to be made of one piece of metal, unlike other fuses which have a brass insert at the top and something inside.How did these fuses work? Could they be dummies for practice rounds? Or are they replicas?
Thanks for any help
Roger

 

[Bever]

These are not dummy fuzes , no.
Pretty sure they aren’t replicas either.

They are for 20mm Incendiary (usually with Tracer) rounds. Basically the Sprengkapsel sits in the top of the fuze & once it breaks on impact it ignites the rest that is inside of the projectile. Added a drawing of this fuze & also an example of what it is used on. As you can see , one of the fuzes still has some blue paint on it. Which makes sense because these rounds are blue too. Mostly with a red band just above the driving band to indicate that there is a tracer.

Theres several other fuze variants of this one. One more common than the other.

I hope this answers your question.

Bever

 

[RogerKP]

Thanks very much for your reply.
I am aware of how the Sprengkapsel works as I have many projectiles fitted with them. The point is, however , that these 2 don't have one - see pictures. They don't have any mechanism inside either. What I really would like to know is how they work, if at all!! Can you help with that?

The fuse with the writing on comes from the round on the right in this picture. I am also unable to identify the round (dated 1941 , which seems a little early for the 151/20?) - could it be phosphorus as I have been told?
Your help is very much appreciated
Roger

 

[Bellifortis]

Hi Roger,
also I can not identify your fuze. even where the left one is stamped "1528A". All 1528 series fuzes are crimped (geboerdelt) in around the top to hold the cap. Both of your fuzes have no crimp on top. Your clear foto of the bottoms lets one discern the rests of some cylindrical steelplate inserts that has been stemmed off where it enters the fuzebody. We don't know what was inside this steelplate-housing. I could not find any fuze, in this size, with such a steelhousing in the bottom.
Regards,
Bellifortis.

 

[Bever]

Well , the most unusual thing about these , or atleast the AZ 1528A you show , is that it has the form of the AZ 1528 . The 1528 has a closed top. The 1528A does not. Like Bellifortis said they are all crimped + the bottom opening is more narrow.

May I ask you what year your fuze is from? Also , the one without markings could very well be a dummy. I’m not sure though. Pretty hard to see to be honest.

added some images so u can see what I mean.

also , the Luftwaffe stamp on your fuze. what number is it? 170 or 70? Just wondering


Please note : by replacement Sprengkapsel I mean an imitation.

last image is not mine , shows the top view of what a closed 1528A should look like.

 

[RogerKP]

Thanks Bever - I'm glad it's not just me that's puzzled by it!

Written around the fuse is: AZ 1528A eea 88 1943, and it's waffenamt is 70. I've just noticed that the interior of the " dummy" is much deeper than the AZ1528A???
Both of these fuses come from incendiaries.


On what sort of a projectile would a AZ1528 have been used?

Roger

 

[Bever]

If the fuze is from 43 it could actually make sense as the early production AZ 1528A fuzes might have still had the form of the regular AZ 1528.

I have no documents that support this theory sadly. But this type of thing also happened with several other fuze types.

 

[RogerKP]

Thanks for your help - much appreciated

 

[Bever]

I forgot to mention the use for these ,

Generally if you look at documents the AZ 1528 is used in 2cm Brandgranate o. Zerl.

The AZ 1528A on 2cm Brandgranate o. Zerl. & 2cm Brandgranate m. Zerl.

But really , I don’t think it would be a mistake & possibly there were regular 1528’s used on the Brandgranate m. Zerl. too.

The 1528 was also used with an adapter for the 5cm Minengranate for SG 500 (Jaegerfaust)

so , for 2cm’s , basically any of these two go on the blue ones with a red band above the driving band or the blue ones with that red band & a green band below the fuze near the top.

 

[Alpini]

Want to add that these fuzes are a pretty much dangerous construction, especially in ground dug condition when the thin protective plate on top is corroded. The fuzes itself have no security mechanism inside. One cartridge fallen on a hard surface or hitting the fuze with a spade could be enough. EOD members take care when dealing with them!

 

[RogerKP]

Thanks
The only problem is that the AZ 1528A is on a red projectile( see above) , not blue! I was told that this is early phosphorus -1941. It’s a similar colour to a night tracer

 

[ron3350]

I am out of my depth in this discussion but I have no references to a red projectile existing as incendiary/phosphorous.
I only have seen blue projectiles. I would not call your projectile red?? Please educate me further. Ron.

 

[Bellifortis]

Hallo,
I looked up some old german airforce manuals to find this strange 20mm fuze. All I could find are a tracer (Leuchtspur) and a dark tracer (Glimmspur). but, strangely the fuze is only named "AZ" without model No., as are all others. Foto is attached. Does anybody have any more info about this fuze ?
Bellifortis.

 

[Bever]

 

[Bellifortis]

Hallo,
the "Leuchtspurbrandgranate"(Incendiary Tracer Shell) seems to be a late war introduction (1943). It was supposed to be used together with the "M-Patrone" to supplant the "Brandsprenggranate". The incendiary-tracer-shell did not contain any explosive, only a thermite-comp. The empty shell stayed intact, even after functioning. The construction is interesting. The only "AZ" named fuze seems to have been charged from the bottom. As @Alpini rightly remarked, this is a very sensitive fuze without any safety devices. The ignition element is a 13mm detonator that normally is ignited by a needlepoint firingpin. The fuze functions already by hitting 2mm cardboard. The technically interesting part is, that the fast detonative impulse of the 13mm detonator has to be slowed down to a hot thermite-ignition stimulus. The functioning of the 13mm detonator shears off the complete fuze and at the same time ignites the thermite in the shellcasing. The thermite-comp burns spraying forwards for 10m flight. The cavity below the 13mm cap is filled with some ignition comp. for the themite. I have not seen any development reports about this fuze and shell. Any additional info would be welcome.
bellifortis.

 

[RogerKP]

Thanks - most interesting!

 

[RogerKP]

Just what I was looking for!

 

[Bellifortis]

I forgot to mention the proper designation for the above pictured cartridge. It is "2cm Brgr.Patr.L'spur 151 o.Zerl.". It was ment to be used only in aerial combat against unarmoured targets. Against armourplate it is ineffective.

 

[Bellifortis]

Attached is a drawing of the AZ 1528 A from an old airforce manual. When you compare this drawing with your 1528A stamped fuze, you see that it is different. Also the internal construction is different. In the drawing a "Zuendhuetchen 1465"(percussion cap 1465) is used as the first ignition element, plus a little ignition-comp. The rest of the fuzebarrel is left empty. Both constructions apparently were used for the "2cm Brgr.Patr.". If anybody has additional info on the "Zuendhuetchen 1465" it would be very welcome.
The unstamped fuze also fits to another construction, the 20 x 80,4 - 2cm MG FF (Oerlikon) which had a brown painted ring above the driving-band. It was used by night-fighters in the "Schräge Musik" assembly.