250 years and they still can go off. Ask any antique gun colloctor. Many old guns were always kept loaded and handed down from gereration to generation without anybody realizing it. Very dangerous. Black powder, as long as it stays dry will never go bad. Even wet and dried out it will still go off. How long you can leave it loaded without damaging the barrel depends alot on the patch lube. You will get a ring of rust right where the ball is seated.
I only unload on a damp day.Don't bring them in from the cold as that produces condensation.Keep them in a unheated area.(Shed,garage,etc)If it is loaded an my rack,I keep a ball starter in the barrel so I know ITS LOADED.
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