Nappen is wrong, in my opinion, in part, and has been wrong in the past. The new gun laws have created new ambiguities which will have to be resolved by the courts if not enjoined. While it is true, that until the end of the grace period, you can possess a mag you own that is in excess of 10 rounds, it is not clear if you can transport that mag in a vehicle. . In my opinion a construction of the law that you cannot during the grace period, is plain wrong, because you may need to transport to dispose of it if you do not or cannot modify it. The only basis on which the police during the grace period could justify not returning them to you is that the return to you somehow qualifies as a transfer and that even during the grace period a transfer not otherwise authorized by law is prohibited. Keep in mind that a magazine, detached from a firearm, is not a firearm although it may be considered contraband if in excess of 10 rounds, after the expiration of the grace period or if it is in excess of 15 rounds before the grace period expires. An interesting question is, if the court issues an injunction on the 10 round limit, will the 15 round limit be effective or no limit. The issue exists depending on how you look at the new law is it a repeal and replace of the 15 limit or a pure amendment to the 15 limit.