The specification discloses a racking arm having a telescoping boom with a supported end and a free cantilevered end. A pipe gripping head is secured to the cantilevered end of the boom for clamping about elongated members such as pipe sections, drill collars, riser pipes or the like. The supported end of the boom is mounted for pivotal movement about a vertical axis and a motor is provided to selectively rotate the boom about the vertical axis. Hydraulic cylinders are provided to selectively raise and lower the free cantilevered end of the boom. Hydraulic cylinders also are provided to extend and retract the boom to selectively vary the length thereof. In operation, the boom is disposed on a drilling rig with the supported end spaced above the working platform of the drilling rig and the vertical axis spaced away from the well bore axis. The boom may then be employed to move elongated pipe members from various storage positions to the well bore or other areas and vice-versa. The pipe gripper head is normally automatically maintained horizontal during vertical movement of the boom. A first embodiment of the pipe gripper head clamps pipe sections, drill collars and the like for lateral movement while allowing the pipe sections and drill collars to slide vertically along their axes. In a second embodiment of the gripper head, riser pipe having an irregular cross-section may be tightly gripped by the gripper head.