Unfortunately, here in Maryland we are limited to 10 round magazines. Unless are you talking about rotary nature of the magazine that comes with the gun? I did buy an extra 10 round magazine so at least I have 2.
Pete
NYC limits us to a special 5 round Mag that Ruger makes - getting caught with a 10 round "standard" mag can get you 3 years. To register a 10/22, you have to prove you own a 5 round mag!!