I tested this bug a few times, I think it's consistent...

If you get on a statgun with a spas it's possible too shoot yourself if you are too close to the barrel...

The other bug is also when you use a stationary gun:
If you keep shooting until the gun overheats, then dismount (still holding down the fire button), the statgun will cool down. But once you get back on, it's instantly red again and it's not possible to shoot (it will only happen if you hold down the fire button the whole time).

I think spyder reported the first one already, and someone else the 2nd, but its good to remind Michal anyways >:P

Also, when you try to keep shooting on the stat gun after it heats up, instead of popping off one bullet as it cools down every once in a while, it just stays hot and never shoots.

Edit: As long as we're talking about the stat gun...if you move your cursor around a lot then, at higher angles, the stat gun begins to shoot a little offset from where you're actually pointing.