German fuze and tracer

I have this ,unknown for me, a new unloaded german fuze, it seem that it was made for the Luftwaffe (bmv “eagle56” 128/42), it look to have a wind’s shield so no sense to be a base fuze.
On which shell does this fuze go with?

and this tracer which was made for the navy ( JZ43 bmv144 "eagleMIII/1), same question


Laurent, above you have a base fuze “Bodenzünder 1512” as it was used in APHE 20x82RR MG FF and 20x82 MG151/20. I think your specimen here was finished (“loaded”) before but just got disassembled by curious “experts” and as so often nothing was put back.
The “tracer” is the “Innenzünder 43” (“internal fuze”) as it was used on the 20x138B and 20x110RR SAPHE-T-SD. A special projectile used only by the navy. The SD feature was initiated by the (separate) tracer which on burn-out reached a tiny powder grain and then blew the primer (in it’s housing) onto the striker.

Here some explanatory material.

Bodenzünder 1512

Innenzünder 43
Drawing and photo by Jakob Lippert (RIP). Photo is also from J.B. Anderhub’s work on the 20x138B cartridge.


Thank you very much Alex, nice drawings!

What is the reason for the use of a moving primer and striker?

It seems that it takes up extra space that could be used for the projectile filling. It also requires extra materials and manufacturing capacity.

Could the self-destruct charge not be simply ignited when the tracer burned out?

Was this system an extra safety mechanism?

The primer/striker is secured by 2 centrifugal pins (below that copper band coil). So that is part of the safety system.