Not bad!
Few notice:
Gun has no inner part, that cause it to drop off on move. I'd rather you make it balanced.
76 kg weight makes it impossible to use in other's scenes (like car smash or something).
Suspension need more damping (and BTW could be done as in real prototype - torsion bars, shock absorbers)
xRay, it's unlimited, but key to success is selection rule.
So you could build anything like round track and choose criteria how to select better performance....