A guide wire luer hub has an elongated hub body with a longitudinal lumen having a plurality of transitions between different lumen sections with different diameters and/or taper angles. The guide wire luer hub is adapted for use with a coaxial guide wire tubing extending from a catheter control handle, where the coaxial tubing has an outer cover or tubing coaxially surrounding a guide wire inner body with a lumen adapted to receive a guide wire, including a guide wire having a floppy, U-bend distal end.