Terrible FPS drops ever since the last update.

Game ran fine until now(Awful bugs but fine) but ever since the last update I get game breaking fps drops when I get fired at by enemy soldiers.

FPS just drops 30-50 frames and I almost freeze for a second when a grenade explodes or an enemy fires at me.

Running:

i5 2500k @4.8 ghz

R9 280x 3gb OC

12gb of DDR3 running at 1886

As I said, issues only started after the last update and maps mostly effected are city maps: Shangai and Dawnbreaker but it happens everywhere.

Changing Graphics settings helps with nothing and mantle just makes it worse.