The invention relates to a holding ring for a blow mould for locking and fixing a plastics material pre-form, with a support face for supporting a collar of the plastics material pre-form and a receiving cavity extending at a right angle to a main extension plane of the support face for receiving a neck region of the plastics material pre-form, wherein the receiving cavity is widened radially outwards in a conical manner at least locally in the cross-sectional area thereof starting from the support face along a longitudinal direction (L) of the plastics material pre-form.