You assume that 1) the carriers of 9mm (or any caliber for that matter) don't already own dozens of 'legal' magazines prior to the law taking effect and 2) that the law isn't poorly worded and entirely unenforceable. BTW, the Glock 19 that I carry is 9mm and comes with completely legal 15rd magazines. Seems like based on that argument the G19 just became a little bit perfecter for conceal carry in the state of Colorado.

