I have tried with a couple different sights and guns now to try and fix / reproduce this bug, i have used 4 different Guns so far, M4, SKS, Mosin, FNX45 and i will go through the problems with the scopes i have tried aswell (PU Scope, BIUS, Acog Scope, Comp82(RED DOT) and the FNX45 Pistol (RED DOT))
(These are over multiple lives,log ins, re-installs and game cache integrity verifications and it doesn't seem to affect my friends)

M4 ACOG - When ever i click right mouse button to aim all i see is the buttstock or some other region of the gun.

M4 Comp82(RED DOT) - When ever i click RMB to aim all i see is the bog-standard M4 Iron sights.

M4 BIUS - Same as above all i see is the bog-standard M4 iron sights nothing else. (not even the ring)

FNX45 (RED DOT) - I only tried this, this morning when i found the sight for it and when i click RMB to view the sight all i get is a zoomed in version of the Iron sights.

SKS & Mosin (PU Scope) - When i used these all i get is the same as above a zoomed in version of the iron sights of both the Mosin and SKS.

( I have posted on one other topic but i feel like the original post was extensive enough )

{F30861} {F30862} {F30863} {F30864} {F30865}