I have my own lock and had it with me. But the dealer said i need to buy one and could not use my own. I have an Omega Internal Gun lock. Sounds like someone was trying to make an extra buck off me. So when I go to pick up my gun in 7 days I will just return the lock and get my money back.
It can't just be a lock either. If the gun does not have one built in, it has to be a bore lock. The through-the-barrel cable locks are not acceptable to Maryland. Best thing is to borrow one, next best, buy one and save it for the next gun of the same caliber that you buy.
The following list are the only approved locks from the Handgun Roster Board.
The statute is also included
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