Foes are considered at range if they are outside of 5ft of each other.
ROF (Rate Of Fire)
For weapons with a ROF of > 1, the attacker must remain stationary in order to take the extra shot(s). Small amounts of repositioning, such as popping out from cover, are fine. The second and/or third attacks will be resolved during the Second Missile Volley.
Ranged Attacks Through Multiple Ranks of Allies
Ranged attacks attempted indoors through more than one rank of allies are usually made at disadvantage. If the attack misses, the GM will roll to randomly determine what ally, if any, the attack might hit.
A Halfing with a crossbow is in the rear of an 8 member party exploring a cramped dungeon hallway. Ahead, the fighters are suddenly engaged in melee with some giant centipedes. Attempting to shoot through multiple ranks of allies will be at disadvantage. They shoot and miss, and a roll indicated the poor mage in the middle ends up the target.
Exception: Set Defense / Shield Wall
Ranks of allies that Set Defense this round can be attacked over without issue.
Ranged Attacks When In Melee
Attacking with a ranged weapon when in melee is possible, but difficult. The attack role is made with disadvantage.
Ranged Attacks Outside of Range
Ranged weapons have an effective range specified. Attacks made between 100-200% of this range are possible, but difficult. The attack role is made with disadvantage. Attacks beyond 2x the effective range are not possible.
Ranged Attacks Into Melee
Attacking with a ranged weapon against a target in melee is not without risk. If the attack misses, the GM will roll to randomly determine what adjacent creature, if any, the attack hits.