A method for manufacturing a barrel arbor (1) used in horology, arranged to pivot around a pivot axis (D). The method including the following steps: taking a bar; profile-turning the bar to form at least one cylindrical portion (13) including a vertical surface and a horizontal surface; machining the cylindrical portion (13) to form the core that includes a hook (2), a support surface (3) and a countersink (4); and simultaneously using a broaching tool by making several translational to-and-fro movements in the direction of the pivot axis (D) of the arbor.