The vehicle isn't Russian. It's the Ukranian T-84 Oplot.

To reproduce this in real life:
1: Obtain an assault rifle.
2: Fire said assault rifle right handed.
3: Observe that the barrel climbs consistently up and to the right.

@Chris: 'Balancing issues' are a problem when you're trying to produce a console game intended to be played by twelve year olds so they can swear at each other on Xbox Live. When you're simply reproducing real-world equipment and aiming to give players an experience where they have to respond to the lethality of the enemy, whether they think it's 'fair' or not (war isn't fair!), then if the vehicle has firing ports, you give it firing ports.

They're supposed to be small-arms resistant run-flats. They currently are not.