A couple words devoted to the gunsight damaging. Usually, a gunsight attached to the turret. It does that at each hit to the turret a game engine started calculation of the gunsight damage probability. No wonder, that after a couple hits a gunsight became damaged. I'd like to suggest to attach gunsight to the mask of the turret through additional chank/dummy, i.e.:
s_sight_holder. In such case a probability of gunsight damaging will be significantly decreased. At least I think so
Here's a picture how gunsight was applied to the turret and another couple screenies. First a turret got two hits and second - three hits. Nor first case neither second a gunsight was damaged.