These are the Hubble screw anchors in which when it comes to rock they are not meant to be placed nor manufactured to be placed in such conditions. A bust or MR anchor are meant for such conditions.
The screw anchors are for soil to firm conditions and nothing more. In order to get the screw anchor in the ground in some rough terrain will require the auger bit pilot hole and the place the screw anchor the rest of the way best you can. At times a hammer may be required but the pilot hole should help quite a bit. Be sure to angle your anchor with the downguy.
I hope this helps
