I am looking way to save the bone move, who uses the Rotation Copy constaraint. when I change the animation frame first bone moves, and bone who copying her movements also, but I can not save these movements. if there is no such a method, it need a simple python script copying bone rotations from bone to bone.
Will you give us little more detail on not being able to save? What do you mean? Can’t key frame?
When marking bone, I pressed the IKEY, keyframes shows in the Action editor, but they does not save rotation caused by Rotation Copy constaraint.
copying rotation is just telling blender to mimic the movements of the main bone you cant save th movement of the copied bone because there is nothing to copy. the key frames are all on the driver bone so if you wanted to copy the movement you wolud need to copy the partent bones keyframes.
if you give us more info on what you are trying to achieve we may have better information for you 
From the beginning, I have finished armature, and the armature with animation bvh. wants to import animations from one armature to another. is it possible? when joined the single bones by Rotation Copy constaraint, everything looked good, so I think that just copy their rotations, but I see that it’s more complicated. someone understands something of this mumble?
BAF.blend (2.12 MB)