The .32-caliber handgun dates back to around World War II. The .40-caliber semiautomatic rifle with a sniper scope and the Chinese-made AK-47, a semiautomatic assault rifle, are modern. And the 12-gauge pump action shotgun could have been purchased off the shelf of a gun store any time in the past few years.
The varying ages of the weapons police say Michael M. McDermott used to slay seven of his colleagues could pose a problem in piecing together how the 42-year-old bearded software tester amassed such a deadly cache.
Still, with help from the federal Alcohol, Tobacco and Firearms Bureau, police hope to determine how McDermott came to possess weapons prosecutors believe he was not legally permitted to carry.
"We're doing our best to track the movement of the weapons, using all the identifying information on the firearms . . . and information on the suspect," said Steve Raber, assistant special agent in the ATF's Boston division. "But some of these weapons are old. Our success depends on contacts with gunmakers."
Initial searches of computer databases in Washington on Wednesday revealed nothing conclusive, Raber said. Agents are trying to contact the weapons' manufacturers, who they hope will lead them to the guns' distributors, retail outlets and to the ultimate buyers.
"If McDermott wasn't the one who bought the gun, we'll find out who did and how they disposed of it," Raber said.
While Massachusetts now has one of the nation's toughest gun control laws, it appears the restrictions did not deter McDermott from obtaining the weapons. He was not permitted to carry any of them, prosecutors say.
The heavyset man obtained a firearms identification card in Rockland in April 1989, Rockland police said. That card would have allowed McDermott to purchase the shotgun, but not the handgun or the assault rifle.
A 1998 state gun control law, which prohibited the sale of all recently manufactured assault weapons, required him to renew the license in 1999. Had he done so, he would have likely been able to acquire all the weapons legally.
Police from Weymouth to Haverhill, where McDermott lived after moving from an apartment in Rockland, said they had no knowledge that he renewed the permit. However, the Globe reported Wednesday that police in Weymouth, where McDermott last lived, issued a Class B license to a Michael McDermott with a slightly different birth date.
If it is the same man, the license would have allowed McDermott to legally purchase a so-called "large capacity" semiautomatic rifle. Despite the state's 1998 gun control law, McDermott could have purchased an older AK-47 with that permit. Police have not determined the age of the weapon.