I’ve found that BP can sure be corrosive even before it’s been burned (fired).
I’ve been wondering what happens to brass loaded with BP after a few years. Being more or less air tight, is the corrosion stopped. Can the power start working on the primer and cause problems?
I’ve always shot all of mine soon after loading, but the other day found one that was a couple of years old and have been wondering if I should pull it apart to protect the brass. Maybe the simplest thing is just to shoot it. Anyway does any significant corrosion take place on the inside of the case?