Please Help me to identify this 90 MM Catridge / Headstamps

[Guest txnith]

Hi,

I recently purchased a cartridge case and I've been told it was made in Belgium 1978 . But my question are:

Headstamps:

what is MJJ-1-1 means ?

90MM NR 5499 A1, does anyone have similar code as mine ? & I wonder how it looks like with a shell. (I hardly can find it anywhere in google)

Primer:

NR 494
BMP -3-
2
4- 77

any thoughts?

Thanks

Txnith

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