A method and machine for making a quick change drill assembly that can be snapped into and out of a spring-loaded ball-locking chuck. The assemblies are comprised of standard sized adapters having various sized bores to receive drills having shanks of corresponding interference-fit diameters. Adapters and drills are fed from opposite ends of the machine to positions from which they are interference fit and automatically discharged. The adapters are fed into a storage tube from a feeder bowl and in the storage tube they are selected or rejected according to the direction of the bore. Selected adapters are air driven to a magazine in a retracted position and from which it is movable to a supplying position. In the supplying position the individual adapter is forced into a radially biasing collet in a hydraulic press. The drills are dropped from a hopper into a slot-bar from which they are pushed into a drill collet in alignment with the adapter collet, the drill being held in the collet by a hydraulic clamping mechanism. The drill shank extends outwardly of the collet toward the bore in the adapter and the adapter is then carried in its collet by a hydraulic ram to be interference fit on the end of the drill shank. The drill is then released in its collet and the adapter collet is retracted to withdraw the drill, secured to the adapter, from the drill collet. The assembly is then pushed out of the adapter collet by a hydraulically operated piston so as to fall into a collecting bin.