The Storm Bolter is a double-barrelled version of the standard Bolter. As it is heavier and causes more recoil than a normal Bolter, it is even more rarely used than the Bolter by the regiments of the Imperial Guard. Instead, Storm Bolters are the standard weapons employed by Space Marine Terminators or as a pintle-mounted weapon on an Imperial main battle tank. Storm Bolters are also used by the Astartes of the Grey Knights Chapter as a gauntlet-mounted weapon with its feed mounted on the rear of their armour. The Storm Bolter also sees limited use amongst the Orders Militant of the Adepta Sororitas, where it is considered a specialist weapon, and favoured by those squads of Dominions, the Sororitas' heavy-weapons troops, who prefer to engage in mid-range anti-infantry combat.
Many Combi-weapon variants of the Storm Bolter exist, such as the Combi-Flamer, Combi-Melta, and Combi-Plasma; these combine a Storm Bolter with another weapon (ie. a Combi-Flamer combines a Storm Bolter with a Flamer). While the Storm Bolter carries as much ammunition as found in stand-alone Bolters, the secondary weapon on a Combi-weapon variant carries only enough ammunition for a single salvo or use.
Due to its high munitions consumption, and the lack of dexterity available to the wearer of Terminator Armour, most Storm Bolters are fed from a large box magazine, carrying approximately 100 rounds. These rounds are identical to those fired from Bolt Pistols and Bolters. Before the Storm Bolter was created by the Tech-priests of the Adeptus Mechanicus after the end of the Horus Heresy, Terminators were often equipped with special Bolters that had advanced targeting equipment and restricted firing rates. These were called Combi-Bolters. They are now only used by the Chaos Space Marines of the Traitor Legions.
Known Storm Bolter Patterns
- Mark III Pattern
- Mark IIIc Pattern, Hecaton Variant
- Mark IV Thunderfury Pattern
- Mark VII Pattern
- Mars Pattern
- Incaladion Pattern
- Ryza Pattern - Storm weapons arose from experiments in combining weapons together to achieve greater rates of fire. The Ryza-pattern Storm Bolter links two bolters to form a single weapon that can shred most foes in a single burst. Rarely seen outside of the Adeptus Astartes, these relic-weapons are typically covered with scripture and purity seals that speak of their ancient origin.
- Umbra Pattern - The Umbra Pattern represents the standard pattern of Storm Bolter employed by the Terminators of most Chapters of the Adeptus Astartes. Their dual magazines have an ammunition capacity of 40 rounds.
- Ultima Pattern
- Nocturne-Ultima Pattern - A modified version of the Ultima Pattern Storm Bolter used by the Space Marines of the Salamanders Chapter.
Adepta Sororitas Patterns
- Mars Pattern
- Godwyn-De'az Pattern - A common Storm Bolter pattern employed by servants of the Ecclesiarchy. This weapon requires two hands to operate and is essentially two separate Bolters capable of firing in synchronised bursts. Its high rate of ammunition consumption makes the weapon impractical in many situations but few would argue with the results that such a powerful symbol of faith can have upon the enemies of the Emperor.
Notable Storm Bolters
- Anmael's Reach - During the Jericho Reach's Age of Shadow, many great heroes of the Adeptus Astartes served the Deathwatch and performed deeds that would have been the basis of legend, had there been any to witness their Vigil. One such warrior was Anmael, a Battle-Brother seconded from the Angels of Vengeance. The stubborn drive of his Chapter led him across the Reach in pursuit of countless inhuman foes. Of his last mission, only the Watch Commander and the Chamber of Vigilance of Watch Fortress Erioch know the details, but he was survived by the ornately worked Storm Bolter he bore from his Chapter’s Armoury vaults. It is said that the Anmael's Reach will suffer no wielder less determined than its first, but its fierce Machine Spirit bolsters the worthy.
- Dorn's Arrow - Chapter Master Pedro Kantor of the Crimson Fists Chapter uses a unique relic Storm Bolter known as Dorn's Arrow. The firing rate of this Storm Bolter is astounding: it is able to fire upwards of 300 rounds in just a few seconds. Because of this, Kantor uses a back-mounted ammunition source, feeding the weapon using ammunition belts that feed into either side of the weapon. Dorn's Arrow is mounted on Kantor's wrist, allowing him to freely use both hands while still keeping his weapon ready to fire.
- Codex: Space Marines (5th Edition)
- Dark Heresy: Ascension (RPG), pg. 140
- Dark Heresy: Blood of Martyrs (RPG), pg. 114
- Deathwatch: Core Rulebook (RPG), pg. 147
- Imperial Armour Volume Four - The Anphelion Project, pg. 124
- Imperial Armour Volume Five - The Siege of Vraks - Part One, pg. 148
- Imperial Armour Volume Nine - The Badab War - Part One, pp. 58, 91, 117, 125
- Imperial Armour Volume Ten - The Badab War - Part Two, pp. 65, 75, 100, 115
- Imperial Armour Volume Eleven - The Doom of Mymeara, pg. 112
- Rogue Trader: Core Rulebook (RPG), pg. 122
- Warhammer 40,000: Wargear (4th Edition)
- Warhammer 40,000: Wargear (2nd Edition)