The Minigun
StA-62 Minigun is a new weapon developed by Stahl Arms in Killzone 3. When mounted, it carries an infinite amount of ammo, but when unmounted, it has a maximum round capacity of 300, which it can burn through rapidly. It cannot be reloaded (unless remounted or resupplied at an ammo box), but boasts a high rate of high-strength fire that can shred infantry with alarming swiftness, and huge damage output as it can even bring the heavily armored Overlord Dropship out of the sky. A negative point is that the gun takes a second to spin up, this can be dangerous when in close quarters combat.
This weapon is most effective against foot soldiers in most missions but will also have a devastating effect on Jet pack troopers and dropships. Its 7.62x51mm pure tungsten rounds deal massive damage to targets.
The Minigun also, like the W.A.S.P, apparently must have a Recoil Reduction system because of it being able to be fired easily. In the Killzone 3 multiplayer it can only be mounted (when repaired by an engineer) but when in the campaign it can be dismounted and causes all hell for Helghast forces as it is deadly to most things the Helghast (or the ISA for that matter) can throw at it. The downside is that you cannot perform brutal melee attacks while carrying it.
The ISA have also been shown to mount scavenged miniguns on their Intruder dropships for use as improvised gunship platforms and laying down suppressing fire.