The Last Gun

A.k.a. Jim il primo. Directed by Sergio Bergonzelli. Starring Cameron Mitchell, Carl Möhner, and Kitty Carver.

Synopsis:

Jim Hart (Cameron Mitchel) has thrown away his gun and vowed not to kill again.  However, danger rides into the peaceful town of Sanderson.  A Band of Outlaws takes over the town and only the sheriff is brave enough to face up to the bandits.  Jim Hart reluctantly picks up his gun to save the town.  With his gun and a mask he stands by the sheriff during crucial moments.  With his help the quiet town of Sanderson regains their gold and can go about its daily business without fear.