The first example of the use of guns to secure a community’s rights that comes to my mind is the Battle of Athens. This is from the Wikipedia article about that event.
The Battle of Athens (sometimes called the McMinn County War) was a rebellion led by citizens in Athens and Etowah, Tennessee, United States, against the local government in August 1946. The citizens, including some World War II veterans, accused the local officials of predatory policing, police brutality, political corruption and voter intimidation.
On a less grand scale, I’ve been told by a fellow engineer (a graduate of Tuskegee Institute) about how his father used a shotgun to protect the rights of his family.
I’m sure the Gentle Readers who know a bit of History can cite other examples.