Some weapons are given a damage bonus when conducting a head shot. This is not consistent across both shield and health as each damage type can have a separate modifier. The chart below shows the weapons which can perform a head shot.
Killing an opponent with a headshot will award +35 bonus XP 
| Weapons with additional Head Shot damage
[Multiplier (maximum damage per shot)] | ||
|---|---|---|
| Weapon | Armor | Health |
| Bolt Pistol / Chaos Bolt Pistol | x 1.42 (40) | x 2.50 (100) |
| Bolter / Chaos Bolter / Relic Bolter / Kraken Bolts | x 0.99 (11)* | x 2.54 (56) |
| Stalker Bolter / Daemon Eye Bolter | x 3.12 (125) | x 2.00 (100) |
| Lascannon / Chaos Lascannon | x 2.25 (225) | x 2.25 (225) |
- Note: Although counter intuitive, the Bolter actually does slightly LESS damage as a head shot against armor, compared to a body shot. The difference is tiny (roughly 0.11 armor) and is not noticeable during normal game settings.
Dreadnought: Rear Armor[]
Several weapons are capable of doing bonus damage to the Dreadnought class. However, the vulnerable location is not the Dreadnought's 'head', on the front of the sarcophagus. Instead the vulnerable location is on the rear of the body, in the 'exhaust' area of the middle torso.