Single-crystal copper wires, 4 mm in diameter, have been produced using the horizontal Ohno continuous casting (OCC) process and a casting regime for the production of single crystals has been established. It was found that at lower casting speeds (< 50 mm min(-1)), single-crystal wires with no visible substructures were produced. However, at casting speeds above 50 mm min(-1), the wire contained unidirectional subtexture and occasional stray crystals. The orientation of crystals parallel to the casting direction tended to be [001] at higher casting speeds (similar to 120 mm min(-1)); at lower casting speeds, the orientation appeared to be random. It was also found that the solidifying wire recrystallized as it emerged from the mould if local strains were inflicted upon the cast surface by mould-strand friction.