Voidshot When rolling To Wound for a weapon that has this special rule, a roll of 6 causes a Wound with the Instant Death special rule. When making an Armour Penetration roll for a weapon that has this special rule, a roll of 6 causes a penetrating hit, regardless of the vehicle's Armour Value.
Sniper If a weapon has the Sniper special rule, or is fired by a model with the Sniper special rule, and rolls a 6 To Hit, that shot is a 'Precision Shot'. Wounds from Precision Shots are allocated against a model (or models) of your choice in the target unit, as long as it is in range and line of sight of the firer, rather than following the normal rules for Wound allocation. A character that has a Precision Shot Wound allocated to it can still make a Look Out, Sir roll. Note that Snap Shots can never be Precision Shots.
If a weapon has the Sniper special rule, or is fired by a model with the Sniper special rule, its shooting attacks always wound on a To Wound roll of 4+, regardless of the victim's Toughness. In addition, any To Wound roll of a 6 is resolved at AP2.
Against vehicles, shooting attacks from weapons and models with the Sniper special rule count as Strength 4.