Apparatus for the hot-chamber die casting of non-ferrous alloys, essentially consisting of: a) a mould made up of two semi-moulds (110, 111), b) a press for closing/opening said mould (110, 111), c) a base carrying said press, d) an injection group comprising: i) a pump body partially or totally immersed in the molten alloy contained in a pot, ii) an injector piston that slides in said pump body, iii) an actuator mounted on a crossbar above said pot and reversibly connected to said injector piston to drive it into a reciprocating motion, iv) a gooseneck formed in the pump body, v) a heated extension arranged at the external end of said gooseneck and provided with a nozzle for the connection to the mould (110, 111), said nozzle being located higher than the opposite end of said extension such that the latter has a slope towards the gooseneck, and e) at least two double-acting hydraulic jacks arranged symmetrically with respect to the extension and secured, with a slope equal to the slope of the extension, between the pump body of the injection group and the portion of said press closest thereto, said apparatus being characterized in that the press is fixed and the injection group is mobile along sloped guides arranged on said base, said sloped guides being parallel to and preferably coplanar with the longitudinal axes of the extension and of said hydraulic jacks, and in that the injection group is divided into a top portion, comprising the actuator and the crossbar, and a bottom portion comprising the pump body, the injector piston and the pot, the latter being mounted on horizontal rails. a) a mould made up of two semi-moulds (110, 111), b) a press for closing/opening said mould (110, 111), c) a base carrying said press, d) an injection group comprising: i) a pump body partially or totally immersed in the molten alloy contained in a pot, ii) an injector piston that slides in said pump body, iii) an actuator mounted on a crossbar above said pot and reversibly connected to said injector piston to drive it into a reciprocating motion, iv) a gooseneck formed in the pump body, v) a heated extension arranged at the external end of said gooseneck and provided with a nozzle for the connection to the mould (110, 111), said nozzle being located higher than the opposite end of said extension such that the latter has a slope towards the gooseneck, and i) a pump body partially or totally immersed in the molten alloy contained in a pot, ii) an injector piston that slides in said pump body, iii) an actuator mounted on a crossbar above said pot and reversibly connected to said injector piston to drive it into a reciprocating motion, iv) a gooseneck formed in the pump body, v) a heated extension arranged at the external end of said gooseneck and provided with a nozzle for the connection to the mould (110, 111), said nozzle being located higher than the opposite end of said extension such that the latter has a slope towards the gooseneck, and e) at least two double-acting hydraulic jacks arranged symmetrically with respect to the extension and secured, with a slope equal to the slope of the extension, between the pump body of the injection group and the portion of said press closest thereto, said apparatus being characterized in that the press is fixed and the injection group is mobile along sloped guides arranged on said base, said sloped guides being parallel to and preferably coplanar with the longitudinal axes of the extension and of said hydraulic jacks, and in that the injection group is divided into a top portion, comprising the actuator and the crossbar, and a bottom portion comprising the pump body, the injector piston and the pot, the latter being mounted on horizontal rails.