Editing Autogun (section)

===Assault Cannon===
[[File:Assault_Cannon.jpg|200px|right|thumb|Assault Cannon]]
The Assault Cannon is a rotary ballistic cannon with an [[Dakka|outrageous rate of fire]], meaning it has to have rotating barrels to stop them from overheating. Although it falls rather short of its terrifying fluffy firepower (consistently going through several ranks of Astartes with each bullet) on the tabletop, the Assault Cannon was buffed up somewhat in 8th Edition. In-lore, this weapon fires unique, diamond-hard rounds at high velocity, resulting in far greater stopping power and armour penetration than might otherwise be expected (hence rending in early editions). Early prototype versions were exclusive to the Imperial Fists and Blood Angels Space Marine Legions, but did have a rare tendency to jam and become useless without some involved repair work. Upgraded jam-free versions were implemented post-Heresy, meaning that Chaos doesn't get these meat-grinders (although [[Obliterators]] do).

Assault Cannons are primarily used by [[Space Marine]]s as anti-infantry weaponry on [[Terminator|Terminators]], [[Dreadnought]]s, and various other vehicles and aircraft. The assault cannon might actually be a stub-weapon, as some art shows it ejecting spent casings. [[Only War]] and several other sources show that there is a difference. Auto-weapons are (usually) caseless and can be anything from merely caseless, chemically-propelled rounds, to railrifles and gravitic-accelerated projectiles. Of course, knowing the Mechanicus, there are probably examples of both auto-weapons and stub-weapons for all solid-projectile weapons of the Imperium.

Being Rotary Cannons, Assault Cannons should in theory be able to spin at different speeds to deliver higher or lower firing rates depending on whether the target is a squishy 'umie or even a vehicle, but this isn't possible in the game. It's possible that the Mechanicus, being the hidebound institution it is, hardwired a one-size-fits-all maximum firing rate in all models of Assault Cannon to make maintenance easier and to keep these weapons from wearing out and overheating too fast, with the ideal firing rate being what a Terminator-armoured Astartes could effectively aim, control, and still be able to carry enough ammunition for in one battle (since faster firing rates also deplete ammunition more quickly). This hypothesis is made more plausible given how the Blood Angels had to resort to mounting twin-linked Assault Cannons in the turrets of their [[Predator_Tank#Baal_Pattern_Predator|Baal Predator Tanks]] to get more of this weapon's firepower in one mount, instead of just spinning one Assault Cannon's barrels faster to achieve the same result as in real life. Though another possible reason might be to achieve the desired rate of fire without the commensurate rise in barrel temperature since making the same barrels fire twice as fast might lead to them distorting from the heat build-up.

{{40k-Ranged-Weapon-Profile-7-8|name=Assault Cannon|r7=24|s7=6|ap7=4|type7=Heavy 4, Rending|r8=24|s8=6|ap8=-1|d8=1|type8=Heavy 6}}
<br style="clear: both; height: 0px;" />