A threaded drill string component having a hollow elongate body with a box end portion, an opposing pin end portion and a cylindrical mid-body portion that extends longitudinally between the respective box and pin end portions and has a variable wall diameter. The mid-body inner wall of the mid-body portion has at least one projecting portion or upset that is spaced from both the box and pin end portions and extends inwardly toward a central longitudinal axis of the hollow body and a plurality of troughs defined in the mid-body inner wall of the mid-body portion.