A child safety seat includes a base, a seat body, a dampening member, and a non-planar impactor. The seat body is slidably secured to the base and is movable between a pre-collision position and a post-collision position. The dampening member is positioned between the base and the seat body. The non-planar impactor is secured to the seat body and is positioned to engage the dampening member. The non-planar impactor and the dampening member together provide a progressive dampening force against movement of the seat body from the pre-collision position to the post-collision position.