Shooter in New York firemen murder used Bushmaster assault rifle

Police are now reporting that the man who ambushed first responders in Webster, New York, armed himself with a Bushmaster AR-15 "assault style" rifle, according to Russell Goldman of ABC News.

William Spengler, 62, was already convicted of murder in 1981 for the beating death of his 92-year-old grandmother, and so was ineligible to own deadly weapons. Nonetheless, local police report that he also had a pump shotgun and a .38 caliber pistol.

The man left a note which stated that he wanted to "do what I like doing best, killing people" and that he wanted to see how much of the neighborhood he could burn down. Police say he died of a self-inflicted gunshot wound to the head.

Investigators also say they intend to find out how Spengler came to possess these weapons illegally. 

The Bushmaster .223 has been involved in a number of high-profile shootings in the US this year — 12 killed in Aurora, Colo., 2 in Portland, Ore., 27 in Newton, Conn. Now 2 firefighters in Webster.

The AR-15 "assault" style rifle was not designed with hunting in mind. The US Army initiated research into the rifle to replace the heavy M14 with a light-weight, high-capacity ground infantry weapon. The basis for the rifle's design was that the Army had concluded that most kills with small arms happen within a range of 300 yards, so planners wanted to maximize the ability for front-line soldiers to kill enemy combatants.

Since the string of shootings, Senator Diane Feinstein pledged to put forward a bill proposal which would renew a ban "assault style" rifles. The bill has a gaping loophole, though, as it grandfathers all assault weapons currently in circulation.

Bill Clinton's ban in '94 left approximately 1.5 million assault weapons in circulation.

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