A method and system for bottom-casting ingots, slabs and the like, in which the moulds are positioned above the discharge orifices of runners extending vertically from communicating mould supply channels extending horizontally within a casting platform. The mould supply channels communicates with a teeming gate arrangement provided with means for selectively cutting off the supply of molten casting metal to the mould supply channels. Further selectively operable closure means are also arranged to co-act with the discharge orifices of the runners, to prevent molten casting metal from rising above the level of said orifices when not covered by a mould.