This guy went to a lot of trouble to off himself. No doubt there are dozens of more-convenient ways to commit suicide. Of course, had this been merely your average handgun-to-the-head scenario, it probably wouldn't warrant much attention here.
An Unusual Zip Gun Suicide—Medicolegal and Ballistic Examination (Full .PDF Journal article)
ABSTRACT: Home-made guns are imitations of typical firearms and usually have handgun characteristics. This article presents an unusual case of a suicide carried out by means of a fatal gunshot wound to the head using a home-made zip gun. A 49-year-old male, with a history of paranoid psychosis was found dead in the dwelling place of a family house. The investigation at the crime scene did not lead to suspicion of a gunshot wound because of the unusual nature of the firearm used. A medical examiner diagnosed an opened head injury as the primary cause of the victim’s death. The autopsy findings provided immediate grounds for further inspection of the crime scene. Subsequently, a simple zip gun, which had been overlooked during the scene investigation, was discovered. An undeformed projectile recovered from the victim’s head was consistent with the use of the home-made firearm. Following the completion of the investigations and autopsy, the death was classified as a suicide.