The gun is Belgian proofed. It was proofed between 1892 and 1924. After 1924 the barrel weight 1K633.3 was no longer done in decimals. They were made by ML, MANUFACTURE LIEGEOISE D’ARMES À FEU.
http://www.littlegun.be/arme%20belge/art...%20feu%20gb.htm

ML produced some very decent guns. They also produced some real clunkers. They were a very large house.

The barrels are fluid steel by Cockerill, a large Belgian steel maker.

Nice looking gun. Interesting single trigger. I do not have enough ML catalogs to id the model.

Pete

http://www.damascus-barrels.com/Movie.html