A Heavy Bolter is a powerful Bolt Weapon that is used for anti-infantry and fire support roles, and is also known as the "Backbreaker" or the "Bruiser" because of its great weight and the amount of damage it can deal. Unlike a Boltgun, it is relatively common in Imperial Guard armies and is also often used by the Space Marines. Heavy Bolters have a high rate of fire and are relatively cheap to field. A Heavy Bolter can also be mounted on the cupola pintle-mounts of a wide variety of Imperial armoured vehicles, as well as act as an anti-personnel weapon by Imperial fixed defences, including strongholds and other fortifications.
Heavy Bolters operate differently to other Bolt weapons. Instead of a firing pin physically striking the bolt shell to activate the projectile, a specific electronic pulse is applied in the firing chamber. Bolts are fed into the chamber by an electric motor, rather than exhaust gases cycling the action as in other Bolt weapons. Exhaust gases are only used to generate the power needs of the weapon; the initial power and the impulse for the first round are provided by working a slide on the weapon's side. These features enable the Heavy Bolter to maintain rates of fire that are physically impossible for a standard Bolter or Bolt Pistol.
The Heavy Bolter has an anti-infantry fire support role in an Imperial Guard unit, and is a very powerful weapon due to the rocket-propelled explosive rounds it fires. Due to its size and weight, it is normally operated by a two-man team in the Imperial Guard. When used by normal Guardsmen, a Heavy Bolter is normally mounted on a stabilising tripod and fitted with a small defensive shield, granting the operators some protection from return fire. Both troopers collaborate to move the weapon and its munitions to new firing positions, and are trained to set it up and begin combat operations in a matter of seconds. Alternatively, unusually strong Guardsmen like Sergeant "Stonetooth" Harker dispense with the tripod and shield, and operate the weapon standing whilst their teammate carries the weapon's ammunition.
Unlike their mortal counterparts, a single Space Marine, being much stronger than a normal man and having the added strength provided by his Power Armour, can carry both the Heavy Bolter and its ammunition in a specially designed pack. Space Marine Scouts can also carry Heavy Bolters and the weapon is especially useful for supplying heavy fire support for Scout Marine sniper teams, as the Heavy Bolter matches the snipers' own weapons range.
The Heavy Bolter fires a .998 calibre bolt, larger than the .75 calibre bolt used by the standard pattern Bolter, and makes use of the same gyro-stabilising technology as the standard Bolter's shells. The Heavy Bolter's casing can also be fitted with weight-reducing anti-grav suspensor studs by Deathwatch Kill-teams, allowing it to be fired on the move; however, its effective range is drastically reduced when fired in this manner. As suspensor technology is very rare, this modification is rarely seen outside the Deathwatch. Various patterns of the Heavy Bolter see use in all branches of the Imperial military, including the Imperial Guard, Space Marines, Sisters of Battle, and all three main Ordos of the Inquisition and their militant arms, such as the Deathwatch.
Known Heavy Bolter Patterns
Over the millennia, Heavy Bolter designs have been improved and changed many times. There exist hundreds of variants, but only a few have made any radical differences in the weapon's function. All of these variant patterns have the same basic features, but each has different additional features, depending on the weapon's pattern, that seek to improve upon its basic design.
- Accatran Mark Vd Heavy Bolter - Manufactured by the Forge World of Accatran, this Heavy Bolter variant is commonly utilised by the Imperial Guard's Elysian Drop Troops Regiments. It features an integral bipod for sustained firing and a sight inside of the carrying handle. The ammunition used by this weapon is intended for anti-vehicle effectiveness: it is self-propelled, mass-reactive, high-explosive, and armour-piercing.
- Asgal Pattern Mark VI Heavy Bolter - A Heavy Bolter pattern only utilised by the Space Wolves Chapter.
- Astartes Mark IVa Heavy Bolter - Based on the original design, this is a commonly used Heavy Bolter variant utilised by the Adeptus Astartes.
- Godwyn Pattern Heavy Bolter - This is a Heavy Bolter variant commonly utilised by the forces of the Imperial Guard.
- Maxima Mark IVh Heavy Bolter - Another commonly used Heavy Bolter variant utilised by the forces of the Adeptus Astartes.
- Requiem Pattern Mk IV - The MK IV Requiem Pattern Heavy Bolter generally sees more use in the hands of the Dark Angel Chapter, their dedication to scripture and lore far-surpassing most other Chapters. The special incense burned in the censor has gained the nickname "Uzziel's breath", and is said to be calming and to sharpen focus.
- Solar Pattern Heavy Bolter - Another commonly used Heavy Bolter variant utilised by the forces of the Imperial Guard.
Chaos Heavy Bolter
Just as the Adeptus Astartes of the Imperium wield weapons beyond the heft of mere mortals, so too do the members of the Traitor Legions arm themselves with larger Bolt Weapons that fire far more powerful rounds. Bolter Weapons used by the Chaos Space Marines are often true relic weapons, possibly even left over from the Horus Heresy itself, and thus are possessed by ancient and murderous Machine Spirits. The blood-thirst of the Traitor Marines' weapons is kept in check only by the formidable will of their fearsome masters. A Traitor Legion Heavy Bolter shares many design similarities with their Loyalist variations, the most sizeable difference being the more powerful rounds and more reliable mechanisms available to the ancient and, in some ways, more advanced models.
- Black Crusade: Core Rulebook (RPG), pg. 157
- Codex: Blood Angels (5th Edition), pp. 57, 59
- Codex: Chaos Space Marines (4th Edition), pp. 81-82
- Codex: Chaos (2nd Edition), pg. 78
- Codex: Dark Angels (6th Edition), pg. 60
- Codex: Dark Angels (4th Edition), pg. 49
- Codex: Space Marines (5th Edition), pg. 61
- Codex: Space Marines (4th Edition), pg. 22
- Codex: Space Wolves (5th Edition), pp. 58-59
- Dark Heresy: Core Rulebook (RPG), pg. 134
- Deathwatch: Core Rulebook (RPG), pg. 147
- Imperial Armour Volume Four - The Anphelion Project, pp. 96, 137, 159
- Imperial Armour Volume Five - The Siege of Vraks - Part One
- Imperial Armour Volume Ten - The Badab War - Part Two, pg. 65
- Rogue Trader: Core Rulebook (RPG), pg. 122
- Warhammer 40,000 Rulebook (6th Edition), pg. 54
- Warhammer 40,000 Wargear (4th Edition)
- Warhammer 40,000: Wargear (2nd Edition)
- Warhammer 40,000: Eternal Crusade - Rogue Trader Store: Requiem Heavy Bolter