Flat nose in 150mm shell

[Piotr]

Welcome,
Anyone of Members have idea what kind of ammo is on pictures. Spec: diameter 15cm, lenght 50.2cm, bottom fuze, two cooper rings. On top its flat ,I think couldnt be balistic cap. Without more information.
Cheers,
Piotr

 

[eodpuds]

Could it just be a "Proofing Round". Any base fuze /tracer ?