Seven Men From Now (1956)

Ex-sheriff Ben Stride tracks the seven men who held up a Wells Fargo office and killed his wife. Stride is tormented by the fact that his own failure to keep his job was the reason his wife was working in the express office, so he is partly responsible for her death. Stride encounters a married couple heading west for California and helps them; along the way they are joined by two ne'er-do-wells, Masters and Clete, who know that Stride is after the express-office robbers. They plan to let Stride lead them to the bandits, then make away with the loot themselves. But they aren't the only ones carrying a secret.

IMDb: https://www.imdb.com/title/tt0049743