Vigilante Force (1976)

In a small town in California, the quiet citizens find their lives disrupted by boisterous, lawless oil-field workers who have infested their community. One resident, Ben Arnold, enlists his brother Aaron, a Vietnam veteran, to assemble a group of men to restore law and order to the town. Though Aaron's crew succeeds, the newfound power goes to some of their heads, and Aaron and Ben must again reclaim the town for the citizens.