Charro! (1969) on Netflix

Vince Hackett's gang steals a prized victory canon from Mexico and blames the deed on ex-gang member Jess Wade who wants to go straight.

With his criminal days behind him, Jess Wade, a rugged horseman who used to ride with the dangerous outlaw, Vince Hackett, and his cut-throats, tries to distance himself from the murderous gang, and go straight. However, no one betrays Hackett. As a result, Vince decides to frame Wade for the theft of the Victory Gun: a powerful cannon of gold and silver that fired the last shot against Emperor Maximilian and freed all Mexico. Before long, Jess finds himself on the run from the Federales, bearing the hideous mark of a thief and hunted down like prey, as Hackett threatens to wipe the small town of Rio Seco off the face of the earth. Now, everyone thinks that Jess is guilty. Can he clear his name and save the town?

—Nick Riganas