In 1952, the ground combat branch conducted at least two live tests of prototype munitions at the Dugway Proving Ground in Utah. The experimental E-83 “radiological bomb” consisted of more than 70 pounds of tantalum 181 pellets wrapped around a high explosive charge, as technicians explained in one report:
The agent was composed of approximately 75 percent tantalum dust … and 25 percent fine copper wire to provide effective binding. The mixture was compressed … in cylindrical pellets. Each pellet had a diameter of 5/16 inch and a height of 5/16 inch.
The pellets were placed in aluminum tubes at the Chemical and Radiological Laboratories [in Maryland] and shipped to Oak Ridge, Tennessee, where the material was irradiated for a time calculated to produce an activation level of three to five curies per pound. The tubes were shipped to Dugway Proving Ground in lead-lined iron containers.