1. Can you make a called shot with a heavy bolter?
Type: Full Action
The attacker declares a location on his target (Head, Body, Left Arm, Right Arm, Left Leg, or Right Leg) and makes a Hard (–20) Weapon Skill Test or a Hard (–20) Ballistic Skill Test.
If he succeeds, he skips the Determine Hit Location step of the attack and instead hits the declared location.
The discussion revolves around the first shot fired.
2. Can you take the aim action with a heavy bolter or any other full auto attack for that matter?
Type: Half Action or Full Action
Aiming as a Half Action grants a +10 bonus to the character’s next attack, while aiming as a Full Action grants a +20 bonus to the character’s next attack.
The next Action the Aiming character performs must be an attack or the benefits of Aiming are lost.
Aiming benefits are also lost if the character performs a Reaction before making his attack.