Here is an animated futuristic air defense gun tower which I have modeled and textured in in 3d-coat. The rig and the antimation I have done in Blender.
The download contains a project file for the Unreal 4 engine and also I have tested everything in Unity 5, the aimations works well as I maded them in Blender 2.77.
Animations:
3 Texture sets: