He is ordered to stay on the post, but tricks a man holding the horses to let him go, his orders were not generally known. He must find the rifles before they are sold to Cochise, as then the outpost would be easily overrun. The brother rejoins his side, and together they over take the men holding the guns and head for the outpost with the guns with Cochise in pursuit. Coburn keeps five repeating rifles (each give the possessor quite an advantage) and sends the brother to the post with the others. He makes good use of the weapons, but still is almost overwhelmed by the Indians.
This show is the kind I loved growing up, with canned military pride of Audie Murphy type. His type of patriotism seems to have been lost. I always look for racism in old Westerns, and I imagine you could find some here. Many Native Americans fall to those guns. But movies are more enjoyable if you don't worry about such things.