lanza didn't have a drum magazine. drum magazines, which feed from two drums, apparently will jam more often.
also, comrade, wouldn't you want everyone to use them if they jam so often? "less chances to kill people"
also you still keep on relying on outliers to justify your position. the fact of the matter is larger magazines allow for people to have that amount of ammo at the ready to deal with situations. mentally disturbed killers are outliers -- of the millions of ar-15s in this country, like three have been used in mass shootings? and that's only because they are popular