An armor plate is provided for use in the ballistic protection of a structure against projectiles incoming from an expected threat direction. The armor plate comprises a layer of pellets made of ballistic material; a gap having a contour at least partially defined by circumferential surfaces of those of the pellets that are exposed to the gap, and occupying an area corresponding to a plurality of the pellets; and an insert inserted within the gap and having an outer surface at least a part of which has an outer shape mimicking the contour of the gap. There is also provided a method for producing the armor plate and an insert for use therein.