blow one's brains out
Shoot oneself in the head, as in Blowing one's brains out is more a man's type of suicide; women lean toward poison. [Early 1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.