The Bushmaster .223 looks like the M-16. I assume it works like one.
The M-16 was selected as the primary assault weapon by US forces because although the ammo for the weapon was relatively light, it had great stopping power. As soon as the bullet enters the body, it starts to tumble for maximum damage, doing much more damage than if it went straight in.
The Bushmaster .223 was designed for one and only one thing - to kill people. It's not designed as a defensive weapon, and certainly not as a home defense weapon.
These weapons should be outlawed.
Would little children still be dead if the shooter wasn't armed with an Bushmaster .223? Yes, no doubt. But I'm willing to bet that the number of people killed would have been lower.
There is no reason for hunters to have rifles that hold more than 3 rounds or hand guns that hold more that 6 rounds.