The idea that in-plane pure shear can be used for reaching infinite forming strains is examined via the bulging process of thin walled tubes. The principal stress ratio of -1 (which represents a pure shear) and other negative ratios were attempted by applying simultaneously internal pressure and axial compression in a synchronized fashion. It turned out that bulging of the tubes with negative stress ratios failed by early buckling of the tubes. On the other extreme, tensile dominated bulging failed by diffused (or localized) necking. An optimized loading path for maximizing the bulging strain between the above opposing trends was experimentally explored, guided by a limit analysis formulation. The experiments were done on Aluminum (Al 5052-0) tubes, using a specially-dedicated machine.