Abstract: To measure the nuclear radiation of a sequence of radioactive samples, magazines that hold sample containers are removably positioned in shuttles, some of which are driven step-by-step by a toothed belt that engages racks on the sides of the shuttles from one compartment to another through a measuring station, with the shuttles that are being driven by the belt driving other shuttles not in engagement with the belt at that time. In the measuring station, the sample containers are released from the magazines one at a time through openings in their bottoms and lowered by a reciprocable support to a position adjacent to a radiation detector for the measurement, after which they are raised by the support to the magazine and the shuttle is driven one more step to the next position.