Commonsense rules. Whenever I travel out of state, I reread each states gun laws, those I will travel through, to refresh my memory. For example: I don't carry through NY if I plan an overnight stop, I stop before entering Illinois to place my unloaded firearm into a locked case, and place the ammo separate from the firearm. Just a few examples. Even with reciprocity, you need to know which states are must declare.
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