Execution by firearms is different than that of execution by firing squad used in the United States. An example would be "single shot from a handgun to the back of the neck" practiced by the People's Republic of China in the past. It has since changed to "single shot from an assault rifle to the back of the head with a special bullet that expands upon impact." It usually results in the disintegration of the upper half portion of the head. See Capital punishment in China for further details.
In Thailand, before lethal injection is being adopted in the 21st century, execution is being carried out by a single executioner firing a mounted Heckler & Koch MP5, which fires in 3 round bursts aiming at the heart of the condemned prisoner.