Abnormal drop of fps in the gunner position

[GAVCA/Jambock__28]

I have a tremendous drop in fps  when I go to the Gunner position and shoot at an enemy (and this enemy shoot me at the same time). The fps fall comes to the point of freezing the image, back to normal only after I was destroyed...

This problem happens even with balanced settings, in SP or MP (but worse in the last).

 

I do not have this problem, in the same situation, in other simulators.

 

Has anyone experienced a similar situation?

 

My configurations:

 

Processor i5 660K

Mem Kingston Gamer HyperX Fury 16GB 

Asus ROG Maximus VIII Hero Motherboard

VGA EVGA GeForce GTX770 SuperClocked w/ ACX Cooling 2GB GDDR5 256-Bit PCI-Express 3.0 SLI - 

Windows 10 64 bits

[Neil]

I use many gunner stations and I do not had this problem

Is your enemy IA or Human or both?