I think the pixel skipping problem is by the design how the marksman rifles work. Even if you're zoomed in the game uses the non-zoomed playerview to calculate the movement of your view.
Explanation:
If you could hide the scope you would see, that your view still moves one pixel, but this then gets multiplied by the zoomfactor of the cameraview of the scope and the cameraview texture projected on your scopelens moves twice as much (4x, 6x with the unlock scopes) so you would have to be able to move 1/2 (1/4, 1/6) pixel "on-screen" to move 1 pixel in the cameraview(scope).
You can try this for yourself:
Get on an empty server (otherwise the marksman role probably will be taken already

), lay down on and rest your scoped rifle on the ground. Now watch the border of your screen and try to move the smallest amount you can (set mouse sensitivity lower if needed). You will see on the edge of your screen, that your view is only moving 1 pixel, but if you then concentrate on the scope and move the same amount with your mouse, the standard scoped rifle will move 2 pixels (unlocked scopes even more).
Fix:
I currently don't know how this could be fixed, probably something like linking the mouse-movement to the cameraview instead of the normal player-FOV, but that is something the coders have to work out.
in most other games this issue is not present because they decrease the fov to achieve a zoom-in and the black out the sides so that you don't notice it, but with that approach you still can move one pixel "in-scope".
sorry for the quite lengthy explanation, I hope you guys understand what I'm trying to tell you.