identification - What are these shell case markings? - History

I have this shell case which was handed down in my family. We know very little about it and wondered if anyone can help identify the markings. I would be very grateful for any assistance.

military - Can anyone tell me anything about the markings on these shell casings? - History Stack Exchange

Large calibre markings (The Western Front Museum)

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WW2 British Artillery Shells and Mortars – Colours and Markings – Stephen Taylor, WW2 Relic Hunter