Abstract: A method for end-to end joining of paper rolls into a continuous core master is provided. The primary goal of the method is to produce usable paper roll cores from those returned for recycling after use. According to the aforementioned method, the ends of core sections are reworked into complementary shapes required for mating a joint, glue is applied to the complementary mating surfaces of the joint, the ends of the core sections are pushed in an axial direction abutting each other and the glue is set. The cross section of the cores is trued circular at least over the area of the joined core sections by applying a radial, compressive trueing force on the joint. The trueing force is also used for braking axial travel of the core sections during the joining of the core sections. An apparatus for implementing the method is also provided.