The Big Bonanza (1944)

Having been falsely court marshaled for cowardice and sentenced to prison by the Army, Jed Kilton escapes and heads to Nevada Springs to see his kid brother. There he meets his old school friend Sam Ballou. But the two old friends soon find themselves on opposite sides and Sam has Jed arrested. Then when Jed's young brother sees one of Sam's men kill another man, the boy becomes Sam's intended victim.