Legislation aimed at reducing and preventing unwanted behavior is only effective if it addresses large loopholes used to circumvent the spirit of the law. A previous ban to high capacity magazines for firearms was bypassed by allowing the sale of magazines made prior to a certain date, but without a manufacturing timestamp on the magazines, it was unknown if they fell under the law and thus allowed to be sold.
Legislation should include 21st century issues for the transfer of items over websites such as eBay. A recent listing of rifle part yields about 20 percent of the auctions being for multiple 30 round magazines for 5.56/223 rifles. The average cost is about $15 per magazine. If nothing is done, this could become a major source for criminally used weapons and magazines.