Glenn, The Federal Law on transporting firearms does not mention Magazines.
Here is what MD says.
“A person may not manufacture, sell, offer for sale, purchase, receive, or transfer a detachable magazine that has a capacity of more than 20 rounds of ammunition for a firearm.” Md. Criminal Law Code § 4-305(b). This section does not apply to a .22 caliber rifle with a tubular magazine. Section 4-305(a).
They don't mention Transporting.
Here is NY Law.
It is a class D felony to manufacture, transport, dispose of, or possess a large capacity ammunition feeding device, which N.Y. Penal Law § 265.00(23) defines as "a magazine, belt, drum, feed strip, or similar device" manufactured after September 13, 1994, "that has a capacity of, or that can be readily restored or converted to accept, more than ten rounds of ammunition." Section 265.02.
In NY the law says Transport. So I believe you would be breaking the law. I only have one firearm with mags that hold more than 10 rounds. It is a Beretta 380 which I never carry except for a backup once in a long while. I will not travel with anything over 10 rounds. Do I have to leave them at home? Maybe, Maybe not but never forget you can be arrested anytime and given your day in court. I won't take that risk when I don't need to.
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