Just saw the movie tonight then read the short story
I have always been a big fan of Elmore Leonard and have read many of his books. Recently, I bought a collection of his western novels that he wrote in the 50s. After watching 3:10 to Yuma again tonight, I immediately read the short (as in 12 pages) story. The names of the Ford and Heflin characters are different in the 1953 story, but some of the minor character's names (Bob Moons and Charlie Prince) are the same. The women of the film are absent in the short story.
Heflin's character in the story is a marshall, though. Ford's character is age 21. Much of the story's dialouge remains in the movie (which was also written by Elmore Leonard). The ending is similar to the movie, but not quite the same.
I actually preferred the film version of 3:10 to Yuma. The slower pace adds to to the suspense and the extended dialogue, always a fine feature in Leonard's stories, adds much to character development. The chemistry between Ford and Heflin is much more evident in the film. The short story seems choppy and rushed. It just didn't flow as well as the movie did.