The invention relates to an increment charge (4) to be placed around a
tail shaft of a fin-stabilized mortar projectile (1), the increment
charge (4) having a centrally located space for the tail shaft and a
mounting opening in the space for mounting the increment charge (4). On
the opposite side of the increment charge (4) there is provided a
protrusion that fits into the mounting opening of an adjacent increment
charge (4) for locking them in relation to each other.