Core for film spool

A cylindrical core for receiving windings of a photographic film web equipped with a peripheral opening for receiving an end of the film web and means for resisting circumferential slippage of a wound film web over the core, wherein said core (1) comprises a hub (3) having an axially extending re-entrant channel (11), an elongated insert (4) fitting into said channel (11) and engaged therein to define with the channel (11) a slot (26) for receiving an end of a film web (2), cooperating detent means (19), (25) for resisting relative axial movement between the hub (3) and the insert (4) when the latter is fitted into said channel (11), the insert (4) incorporating means (24) projecting into said slot for engaging at least one marginal perforation of said film web end to prevent circumferential slippage of the film web (2) and being disposed so as to disengage from such film web perforations when the film web extends radially of the hub periphery on unwinding.