Civil War cannonball kills Virginia relic collector

"I used to laugh at him and say, 'Why do you watch this? You know how it turned out. It's not going to be any different,'" Brenda White said.

She didn't share her husband's devotion, but she was understanding of his interest.

"True relic hunters who have this passion, they don't live that way vicariously, like if you were a sports fanatic," she said. "Finding a treasure is their touchdown, even if it's two, three bullets."

Union and Confederate troops lobbed an estimated 1.5 million artillery shells and cannonballs at each other from 1861 to 1865. As many as one in five were duds.

Some of the weapons remain buried in the ground or river bottoms. In late March, a 44-pound, 8-inch mortar shell was uncovered at Petersburg National Battlefield, the site of an epic 292-day battle. The shell was taken to the city landfill and detonated.

Black powder provided the destructive force for cannonballs and artillery shells. The combination of sulfur, potassium nitrate and finely ground charcoal requires a high temperature — 572 degrees Fahrenheit — and friction to ignite.

White estimated he had worked on about 1,600 shells for collectors and museums. On the day he died, he had 18 cannonballs lined up in his driveway to restore.

White's efforts seldom raised safety concerns. His wife and son Travis sometimes stood in the driveway as he worked.

"Sam knew his stuff, no doubt about it," said Jimmy Blankenship, historian-curator at the Petersburg battleground. "He did know Civil War ordnance."

An investigation by the Bureau of Alcohol, Tobacco and Firearms will not be complete until the end of May, but police who responded to the blast and examined shrapnel concluded that it came from a Civil War explosive.