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That a man who worked as a trucker made a 1,300-mile drive is perhaps unremarkable. But John Coster-Mullen's destination, and motivation for heading there, were unusual. As NPR reports, Coster-Mullen in 1993 decided he could capitalize on the looming 50th anniversary of the atomic bombs that fell on Hiroshima and Nagasaki by making small replicas to sell.

But after realizing the currently available versions had what he identified as deviations from the true design, he decided to head to Los Alamos, NM, to view the replicas held in a museum there.

He never ended up selling his models, but he did pen a 431-page book that NPR describes as "basically complete specs for America's first nuclear weapons"; as David Samuels explained in a 2008 New Yorker profile, the US government has kept those specs under wraps.

To arrive at his own, Coster-Mullen pored over declassified photos (he insists none of the info he has come by was leaked); interviewed machinists, scientists, and engineers; attended reunions of the servicemen who dropped the bombs; analyzed bolts and screws; and much more.

Among the more: Upon arriving in Los Alamos, he found the area of the museum he wanted to access closed for renovations; he ultimately gained access and spent hours with his son measuring bomb casings.

The result is the book Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man, which Samuels wrote has a "mind-numbing" but "strangely seductive ... accumulation of detail. ... I felt that I could practically assemble an atomic weapon myself." And that's the point.

"It is so easy," Coster-Mullen, now 71, tells NPR. "The hard part is creating the nuclear fuel." (The original US nuclear tests actually messed up Kodak film.)

This article originally appeared on Newser: How a Truck Driver Figured Out Complete Atomic Bomb Specs