America's lethal weapon of choice

IN AROUND eight to 10 minutes, Adam Lanza fired hundreds of rounds in the Sandy Hook Elementary School from a Bushmaster AR-15, killing 20 students, six staff and himself. According to the Connecticut medical examiner, the seven victims he performed autopsies upon had been shot between three and 11 times each.

An AR-15 jammed in the hands of a killer in Oregon the week before last, preventing him from killing more than two. Another was used in the July shooting in a Colorado cinema in which 12 people died and 58 were injured. Martin Bryant used an AR-15 in Port Arthur.

It has become the most popular rifle on the US market and is the weapon now targeted by American gun control advocates. When politicians talk about military-style rifles, or assault rifles, or even semi-automatic rifles, this is invariably what they are talking about.

The AR in the name comes from ArmaLite, the company that originally built the gun for the US military before selling the rights to Colt in 1959. The military version of the AR-15, the M16 and the M4, has been the US military's primary weapon ever since. Variants of the rifle are now made by many manufacturers, including Bushmaster, which made the model used in Sandy Hook.

The AR-15 is high-powered and lightweight and comes with magazines holding 10, 30 or even 100 rounds. Though often used for target shooting or hunting, much AR-15 ammunition sold in the US is designed to break up and tumble through the human body on contact to cause maximum damage.

It is sometimes described in gun circles as a "Barbie Doll for men" because of the number of accessories available, including a grenade launcher.