The device comprises a casing (2, fig 4a), a syringe carrier (8) located within a proximal end of the casing and being movable along a longitudinal axis of the device between a stowed position and a needle insertion position, and a drive assembly (10) located within adistal end of the casing and being movable by an insertion driver in order to move the syringe carrier and a loaded syringe from a stowed position to a needle insertion position. The device further comprises a first formation 36 fixed relative to the casing and a second formation 34a fixed relative to an insertion tube of the drive assembly which define a plurality of stop positions for the insertion tube and prevent significant rearward movement of the insertion tube along said axis when a plunger of a firing cartridge is released from a reaction assembly of the cartridge. The device further comprises a clip (33, fig 8a) expandable against the casing to produce an audible click at the end of travel of the plunger.
