When you have focus press CTRL and you cast Barrage
SINGLE TARGET
/targetenemy [noharm][dead]
/cast [modifier:ctrl] Barrage
/castsequence [nochanneling] reset=5 Aimed Shot, Steady Shot, Steady Shot
/castsequence [nochanneling] reset=9 !Chimaera Shot
/use [combat] Rapid Fire
AOE
/targetenemy [noharm][dead]
/cast [modifier:ctrl] Barrage
/castsequence [nochanneling] reset=5 Multi-Shot, Steady Shot, Steady Shot
/castsequence [nochanneling] reset=9 !Chimaera Shot
/use [combat] Rapid Fire