The company expanded, taking over foundries at Grundhof, in the Red Lands, at Eich, and at Fischbach.He first became involved in politics through his opposition to the Third Partition of Luxembourg in 1839.
In 1848, Metz sat on Luxembourg's Constituent Assembly, and then the first Chamber of Deputies, elected in 1848 to represent Grevenmacher.
He was targeted in the 1854 election by the Simons government.
He would not live to see the assembly of the new Chamber of Deputies, however, as he died in Eich just eight days after the election, having fallen ill inspecting the foundry at Berbourg, exacerbated by tonsillitis.He married Petronille Laeis on 17 August 1841.