"There is an allure to this weapon that makes it unusually attractive," said Scott Knight, former chairman of the International Chiefs of Police Firearms Committee. "The way it looks, the way it handles it screams assault weapon."
Knight, who also is police chief of Chaska, Minn., said the gun's practical application is little more than "a combat weapon."
"Simply put, it can get off a large number of rounds in a matter of seconds," Knight said. "That's what makes it attractive and also so dangerous."
In the school shooting, Connecticut Chief Medical Examiner H. Wayne Carver II said all 26 victims were hit multiple times, suffering "devastating" wounds and all apparently traced to the rifle.
Connecticut State Police Lt. Paul Vance said Sunday that the shooter used "multiple" 30-round rifle magazines in the attack.
The weapon, Carver said, delivers bullets "designed in such a fashion (that) the energy is deposited in the tissue so the bullets stay in."
"I've been at this for a third of a century and my sensibilities may not be the average man, but this probably is the worst I have seen," Carver told reporters.
Because the exact specifications of the weapon are not publicly known, it is unclear whether the actual weapon would have been prohibited under the former federal assault weapons ban which expired in 2004. Though, the law would have prohibited the 30-round magazine.
But Jonathan Lowy, director of the Brady Center's Legal Action Project, said the type of firearm is what gun-control advocates have sought to ban.
"There's a reason why these types of weapons are useful for the military," Lowy said. "They have the capacity to massacre large numbers of human beings in a short amount of time. There is little or no use for these weapons for people who want to use them for self-protection or sport."
Representatives of the National Rifle Association and the National Shooting Sports Foundation did not respond to requests for comment Sunday. Bushmaster Firearms International in North Carolina also could not be reached for comment.
The Bushmaster brand rose to unusual prominence in 2002 when it was learned that the two gunmen in the Washington-area sniper shootings used the semiautomatic weapon in its series of assaults in the region.
John Allen Muhammad and Lee Malvo were convicted in the shootings (Muhammad was executed in 2009). And a civil lawsuit resulted in a $2.5-million judgment against Bushmaster and a Washington state gun dealer where the weapon was stolen.
According to the settlement, Bushmaster paid $550,000 of the total award. Lowy said the case marked the first time a firearms manufacturer agreed to settle a case related to a gun used in a crime.
At the time of the settlement, Bushmaster maintained that the settlement was not related to any wrongdoing by the company.