A rotating cone drill bit includes a plurality of mud nozzles extending from the bit body, which are thermally fitted by controlling the temperature differential depending on the corresponding materials, the amount of fit desired, and the diameters of the elements to be fitted and which provide substantially obstruction-free mud paths toward the wellbore bottom. The bit has a plurality of reduced diameter cutter assemblies, each having a journal projecting from a corresponding leg. The journal has at least two cylindrical bearing surfaces and an annular groove formed therebetween and a spindle. An annular retention segment is rotatably mounted in the groove. The retention segment has an outer radial surface engaging a portion of one of the bearing surfaces of the cone, and an energy beam welding area fusing substantially the entire engaging surfaces of the retention segment and the cone.