Hands Across the Border (1926)

Cattle rancher John Drake sends his son, Ted, to the Mexican border to stop the smuggling that is using Drake's land as the crossing point. Ted meets Ysabel Castro, the daughter of the rancher just across the border-river, when he saves her from a mad-bull. He captures a messenger for the smugglers, captures him and then goes to the gang's camp posing as the messenger. They soon find out he is an impostor, and he and Ysabel and her father are lined up before a firing squad. Maybe Silver King can summon the Calvary.