The design specifications were completed in February 1945, and contracts were let to build the components. Three different plants were used so that no one would have a copy of the complete design. The gun and breech were made by the Naval Gun Factory in Washington, D. C. ; the target case and some other components by the Naval Ordnance Plant in Center Line, Michigan; and the tail fairing and mounting brackets by the Expert Tool and Die Company in Detroit, Michigan. The bomb, except for the uranium payload, was ready at the beginning of May 1945. Manhattan District Engineer Kenneth Nichols expected on 1 May 1945 to have uranium-235 "for one weapon before August 1 and a second one sometime in December", assuming the second weapon would be a gun type; designing an implosion bomb for uranium-235 was considered, and this would increase the production rate. The uranium-235 projectile was completed on 15 June, and the target on 24 July. The target and bomb pre-assemblies (partly assembled bombs without the fissile components) left Hunters Point Naval Shipyard, California, on 16 July aboard the heavy cruiser USS Indianapolis, arriving on 26 July. The target inserts followed by air on 30 July.