Nobody here says what version they're playing but V4.12 comes with a 6DoF installed through the control board. It's found under the "Pan View" section and is called "Head Movement." You need to tie a button or key(s) to activate it (I use a button on my joystick). You then, while holding the key(s) or button, use you mouse to move your head left, right, forward, and back. Again, holding the key(s) or button, use the mouse wheel to move up and down. With this you can align the ring and bead sights.
A simpler approach of course is to use TrackIR or something like it.
These sights have save my a$$ more times than enough.
Bob