Why was George S. Patton penalized in the pistol-shooting event at the 1912 Olympics?

At the 1912 Stockholm Olympic Games, George S. Patton was penalized in the modern pentathlon shooting event because one of his shots was recorded as a miss.1

Patton, who used a heavy .38-caliber pistol rather than the .22-caliber weapon preferred by most other competitors, argued that the missing shot had actually passed through one of the existing holes made by his previous rounds. However, the referees were unswayed by his protest and maintained that the shot had gone astray, resulting in a penalty that ranked him 21st in the shooting portion and left him in fifth place overall.1