Plot hole in the Plot hole
In the "Goof" section there is a "Plot Hole" that reads: "It would have been easy to tell that Valance had been killed by a bullet fired from a rifle, not a bullet fired from a revolver."
Stoddard was carrying a Colt 1862 Navy Cartridge Conversion, which was able to fire the 38 WCF cartridge. Tom used Pompey's Winchester model 92, which also came in the 38 WCF cartridge.
Since the only medical attention that was given to Liberty was "Whiskey, Quick!!........Dead" I doubt they called out 'CSI: Shinbone' to do ballistics tests.