The grav-cannon is a heavy Imperial weapon that fires a focused gravity field instead of a shell. It’s built to wreck vehicles and power armour without setting off ammo or fuel, which makes it a favourite of Space Marine Devastators and the Adeptus Mechanicus.
What the grav-cannon actually does
It’s a graviton projector. Instead of punching a hole, it spikes local gravity hard enough to crush what’s inside. That ruptures organs and cracks bones even through ceramite, so infantry caught in the beam don’t walk away.
The real point is anti-materiel work. Gravity doesn’t care about fuel tanks or magazines, so a grav-cannon can disable a tank or a Dreadnought without the secondary explosions you’d get from a lascannon or missile launcher. It’s cleaner, and often quieter.
Who carries it
Space Marine Devastators are the classic users, and you’ll also see grav-cannons mounted on Rapier carriers and Centurion warsuits. That covers the mobile, heavy-infantry side of the Imperium.
The Adeptus Mechanicus fields bigger versions. Their Heavy Grav-Cannons appear on Kataphron Destroyers and can be wielded in pairs by Tech-Priests. The Mechanicus versions hit hard enough that a single blast has been recorded breaking an Obliterator in two.
- Space Marine Devastators: standard grav-cannon teams.
- Rapier carriers and Centurions: mobile or armoured mounts.
- Adeptus Mechanicus: Heavy Grav-Cannons on Kataphron Destroyers and Tech-Priests.
How it fits with other grav weapons
The grav-cannon sits in the same family as the smaller Graviton Gun and the larger Graviton Blast Cannon. Same principle, different scale. The gun is lighter and more portable, the cannon is the workhorse heavy option, and the blast cannon leans toward siege and anti-armour.
Don’t confuse it with the Graviton Cannon, which is a separate, larger gravitational projector in the same lineage. Sources use the names loosely, so if you’re list-building, check the datasheet rather than the label.
Why it matters on the table and in lore
Grav weapons give Imperial forces a way to strip armour and vehicles without relying on explosive warheads. That’s a big deal when you’re fighting inside a hive, a ship, or anywhere a stray detonation could kill your own side.
In the fiction, they’re a reminder that the Imperium’s tech isn’t all brute force. Gravity manipulation is old, well-understood science to the Mechanicus, and the grav-cannon is one of its most practical battlefield expressions.
Key facts
- The grav-cannon is a heavy graviton projector that crushes targets with focused gravity.
- It’s prized for disabling vehicles and power armour without secondary explosions.
- Space Marine Devastators, Rapiers, and Centurions are common carriers.
- The Adeptus Mechanicus uses Heavy Grav-Cannons, powerful enough to break an Obliterator in two.
- It belongs to the same family as the Graviton Gun and Graviton Blast Cannon.
FAQ
Is the grav-cannon the same as the Graviton Cannon?
Not quite. The Graviton Cannon is a larger gravitational projector in the same family. The grav-cannon is the heavy weapon you’ll see on Devastators and Mechanicus units.
What’s the grav-cannon best at killing?
Vehicles, battlesuits, and heavy infantry. It crushes armour and internals without causing secondary explosions, which makes it ideal for boarding actions and urban fighting.
Who can take a grav-cannon in Warhammer 40k?
Space Marine Devastators, Rapier carriers, and Centurions are the common Imperial users. The Adeptus Mechanicus fields heavier versions on Kataphron Destroyers and Tech-Priests.