𝑀-type hexagonal ferrite precursor was prepared by a soft mechanochemical treatment of BaCO₃ and 𝛼-FeOOH mixtures. The effect of milling on its structure and thermal behaviour was examined by XRD, SEM and FTIR. Well crystallized 𝑀-type hexagonal ferrite was formed from just 1 h milled precursors at 800°C. The beneficial effect of milling was explained in terms of increased homogeneity with simultaneous hetero bridging bond formation between powder constituents.