A medicament delivery device includes a housing having a longitudinal axis, a container holder, an axially movable plunger adapted to be displaced along the longitudinal axis into the container holder, and an energy accumulating member arranged inside the housing and adapted for displacing the plunger along the longitudinal axis. The plunger includes an outer plunger rod and an inner plunger rod arranged at least partially inside the outer plunger rod, the inner plunger rod being threadedly engaged with the outer plunger rod and manually rotatable to displace the inner plunger rod along the longitudinal axis into the container holder.