hip-shooter

hip-shooter

Someone who speaks or acts rashly, recklessly, or bluntly, without consideration of potential consequences. An allusion to firing a handgun immediately upon drawing it from its holster without taking time to aim. The country's prime minister has gained a reputation as a hip-shooter, issuing executive orders without consulting members of parliament. The boss tends to be a hip-shooter, so don't take what he says too personally.
Farlex Dictionary of Idioms.

hip-shooter

n. someone who talks without thinking; someone who speaks very frankly. (see also shoot from the hip.) He’s just a loudmouthed hip-shooter. Pay no attention.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • fire from the hip
  • shoot from the hip
  • Earth to (someone)
  • earth to someone
  • like a bull at a gate
  • baton
  • hand on the baton
  • get in/into one's hair, to
  • fight (someone or something) hammer and tongs
  • fight hammer and tongs