so you only need this during a zombie invasion or great Britain trying to take over the country.
This guy was stopped during the reload process. I think its very likely less peolple wuld of been hurt/killed had he not had access to this magazine.
And if the proper records had been made he never would have. But gun laws are more exciting then procedural errors, so by all means blame them for the problem.
Zombie invasion?
Hurricane Katrina. It happened.
The Rodney King Riots. They happened.
Other riots have happened in various locations where groups of people have engaged in destruction of property.
Home Invasions involving several determined people. Rare, but they happen as well.
Criminals acquiring already illegal automatic weapons and using them to kill people. Happens quite often regardless of the restriction of automatic weapons sales to the mainstream populace (which has been around for close to a century).
And if your only criteria is hypothetical body count, say one day I'm living in a hurricane zone and use a 30 round mag to stop a gang and save lives. Will that even things out for you?