Abstract: The drill/countersink nosepiece assembly of the present invention permits the fabrication of a precise hole and countersink in a structural assembly workpiece in a single operation with the aid of a drill plate or other hole template. The small size of the nosepiece tip enables multiple holes to be closely spaced without interference between drill plate engagement slots. A close fit between the shaft of the rotating drill/countersink bit and the inner surface of the sleeve prevents the bit from wandering upon repeated or heavy use. The drill/countersink nosepiece comprises a combination drill/countersink bit to be received by a drill motor chuck, a bushing to be received by a fixed housing portion of the drill motor, a sleeve telescopically mounted within the bushing, a spring within the bushing to bias the sleeve forward, and fingers or other features at the end of the sleeve for engaging an alignment slot in a drill plate.