Beirut FCO (Fire Control Orders). aka Beirut salute.
A method of fire control popularised in the late 70s and early 80s by the militias of Beirut.
The method involves taking cover behind a barricade or car, holding your AK 47 above your head pointing in the general direction of the enemy and blatting the contents of the magazine in one long burst. Obviously not being supplied by the MoD!
See also Pray and Spray.