Code of the Silver Sage (1950)

""ROCKY" CHAMPIONS THE RANGER'S CODE IN A BLAZE OF FIGHTING FURY!"

Arizona Territory is in the grip of outlaw terror and killer outlaws, secretly organized by Hulon Champion, who covers his power ambitions with the guise of a respectable firearms merchant. Hoping to eradicate the lawlessness plaguing the newspaperman Fred Gately prints a letter asking the president to visit the area. But Fred's killed by secret gang leader Champion, who also plans to assassinate the president. Undercover officer Rocky Lane teams with his assistant, Nugget, and Fred's spunky daughter to combat Champion's head gunslinger.