A method for the shaping of plastics material pre-forms into plastics material containers, wherein the plastics material pre-forms are introduced into a blow mould and are expanded to form the plastic bottles by being acted upon with a gaseous medium in the blow mould, includes the steps of: preliminary blow moulding by acting upon the plastics material pre-forms with a first pressure; intermediate blow moulding of the plastics material pre-forms at a second pressure which is higher than the first pressure; and final blow moulding of the plastics material pre-forms at a third pressure which is higher than the second pressure, wherein at least the second pressure is varied during a working operation.