The invention relates to a method for inserting a plunger (6) into a container (25), in particular a container (25) of a dispensing cartridge. Firstly, a plunger (6), the outer circumference of which is provided with at least one elastically deformable seal (17), is inserted into a setting tool (1), the at least one seal (17) of the piston (6) being elastically deformed radially inwards in the setting tool (1). The setting tool (1), together with the plunger (6) held therein, is then inserted into the container (25), allowing air to escape from the container through at least one venting opening (11) and finally, the plunger (6) inside the container (25) is ejected from the setting tool (1), thus allowing the at least one seal (17) of the plunger (6) to elastically expand radially in order to lie against the inner face (26) of the container (25).
