When I spawn into a server with the SKS in my hand (PU-scope on it) and the Mosin on my back (with a LR-scope on it) I regularly get this glitch where zooming down the PU-scope causes me to look at my fist.
Taking off the PU-scope and putting it back on does not resolve the matter
I actually have to put the PU-scope on my Mosin, then take it off again and put it back on my SKS.
See video for details.
https://www.youtube.com/watch?v=-OOlqBjYM_U&feature=youtu.be