57mm Gruson case

[Vasco Da Gama]

I almost walked past this case in a junk shop but the lack of any markings and the primer made me part with my pocket money. I think it is a 57mm Gruson case, beyond that I am stumped. Glad to be educated if somebody can tell me more about which country may have used completely unmarked ammunition. Pictured alongside a WW1 53mm German made Gruson case. The 57mm case is 252mm long, rim 73mm and mouth 58mm.

 

[Hoeksel]

If it is 250 mm long it is indeed a 5,7 cm Gruson L/25 case as used by several nations. Primer layout is possibly the identifier.