A joint for a cardiac stimulation lead is disclosed that connects a lead body and a coil conductor with an isodiametric junction. The lead body includes a counterbore disposed at its distal end. The lead body's counterbore securably receives the inner insulator of the coil conductor. Alternatively, the coil conductor includes a counterbore disposed at its proximal end. The coil conductor's counterbore securably receives the distal end of the lead body.