I once worked with a woman who shot herself to death using a rifle or shotgun (I know almost nothing about guns, so I don't know for sure what kind it was). She used her big toe to pull the trigger. She was an embezzler and found out that the company knew what she was doing. Rather than face the consequences of her actions she committed suicide leaving behind two teenage children and two toddlers. Everyone was completely shocked both by the embezzlement and the suicide.
In her case, she probably chose a firearm "to be sure," so she wouldn't be revived and prosecuted.