It is the night before a major Civil War battle but when Corporal John Warner (George Hilton) learns that the woman he loves is seriously ill and about to give birth to his child he goes AWOL. After various struggles to make his way to her John returns, but it is too late as his girlfriend is dead and her father Don Pedro Sandoval (Ernest Borgnine) blames him for her death, ordering him and his friends to leave with the baby. It makes things difficult as there is a Cholera epidemic and no one is willing to help them with lodging or food. When John's child becomes sick and dies he makes it his mission to make all those who turned him away and also Sandoval pay for what they did.
When you say spaghetti western to a lot of people they think of a mix of those made by Sergio Leone with that classic styling and those which were poorly dubbed in the 70s. The thing is that not all spaghetti westerns were blessed with either great directors or curse by bad dubbing and editing and as such there are a lot which are like "A Bullet for Sandoval", simply middle of the road. From the storyline of a man seeking revenge to the camera work as well as the acting there is nothing memorable about it and to be honest there are times where it doesn't do enough to keep hold of your attention.
As such what you get in "A Bullet for Sandoval" is an uncomplicated tale of a man who in need of help finds the door figuratively slammed in his face time again from those who won't spare food or offer a room for him and his baby son to rest up. As such when what is special is taken from him he seeks revenge on those he blames for not doing enough to help. Aside from that there is no real great action, no memorable characters or believable acting and the twist which sees Sandoval hire men to go after Warner adds nothing to the movie other than a few more scenes for Ernest Borgnine to play it as an angry, heart broken father.
What this all boils down to is that "A Bullet for Sandoval" ends up one of those spaghetti westerns which offers nothing out of the ordinary and in truth is now the sort of western you watch once if you have never heard of it and like spaghetti westerns but after that you know you will not return to watch it again.