The invention relates to a needle storage magazine (1) for storing a number of injection needles (3.1, 3.2, 3.3) and attaching and/or detaching them to or from an injection device (14), the needle storage magazine (1) comprising a crescent shaped track having a convex part and a concave part, wherein the track is adapted to hold a set of needles (3.1, 3.2, 3.3) in respective needle supports (6) within the track, wherein the convex part is adapted to hold unused needles (3.1) and used needles (3.3), wherein a centre position (B) is defined within the concave part for a needle (3.2) in use or to be used, wherein a sliding carriage (17) is arranged for attaching the injection device (14) to the needle storage magazine (1) such that the centre position (B) is essentially concentric to a longitudinal axis (5) of the injection device (14), wherein a separation wheel (7) is rotatably arranged, the separation wheel (7) having at least one notch (15) for entraining the needle support (6) of one unused needle (3.1) at a time from the convex part into the centre position (B) or the needle support (6) of the needle (3.2) in use out of the centre position (B) onto the convex part.
