The boltgun is the defining firearm of the Adeptus Astartes, a weapon so bound to their legend that to hear its roar is to know the Emperor's angels have come. It does not fire simple bullets. Each round, called a bolt, is a self-propelled rocket tipped with a mass-reactive charge. The shell buries itself in armour or flesh under the force of its launch, ignites its own motor, and detonates deep inside the target, blowing the victim apart from within.
Firing such ammunition demands a heavy, thick-barrelled weapon with brutal recoil, and few unaugmented humans can wield a true bolter without being knocked from their feet. In the gauntleted hands of a transhuman warrior it becomes an extension of will, hammering out a storm of detonations that shreds infantry and cracks light vehicles alike. The sound alone — a deep, staccato thunder utterly unlike the crack of a lasgun — has broken the nerve of countless foes before a single shot lands.
Countless patterns exist across the Imperium, from the revered relic-weapons of the First Founding to the mass-forged variants issued to newer Chapters. Bolt weapons are also carried by the Adepta Sororitas, Inquisitorial retinues and the most honoured Astra Militarum officers, each round blessed and inscribed by tech-priests before it is chambered. To bear a boltgun is to carry a piece of the Imperium's faith made manifest — a promise that its enemies will be answered not with mercy, but with fire and fury.