Perry:

When you say percussion, do you mean rim-fire like a 9mm Flobert? Could "EB" in an oval be the Belgian mark which has a "ELG"? 16mm(16.2 & 16.6mm) would be 16 bore which is typical of European. It's hard to say without pics. For now I'll guess Wundhamer to be a firearms merchant. I think I recall Reid of Austria be near a DP(Displaced Persons) camp.

Kind Regards,

Raimey
rse