Barrel lengths may vary from state to state without regard to federal legal length.
Just as Kalifornicate will not allow a private citizen to have a magazine that can hold more than 10 rounds.
(I did not say "high capacity" on purpose. If a firearm is designed to hold 13 - 15 rounds, then a 13-15 round magazine is not high-cap, but "normal capacity". If the firearm was designed for 13 rounds, and the mag holds 26, then it is "high capacity".)
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
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