This gun was proofed in Belgium. I believe it was proofed in 1954. But it is missing proof marks. I think Raimey is correct. The cold war was heating up. It could have found it's way into a country that did not recognise the Brussels Convention and was reproofed there.

Hopefully, Geno or Jani can jump in here. I have nothing on those Y and U marks.

Pete

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