Here's the link to the video showcasing the 1x & RAPTAR issue:
https://drive.google.com/file/d/1FNGwitkERloFceYyXn5iYnFp6WNdJNYX/view?usp=sharing
RAPTAR must be already enabled on the weapon for the bug to reproduce.
It also happens with non-RAPTAR weapons that have zoom-toggleable scopes, but only if you don't ADS with the non-RAPTAR weapon when you swap back into the RAPTAR enabled weapon. Once you ADS with the non-RAPTAR weapon's scope, the issue doesn't occur on the RAPTAR enabled weapon when you switch back. With the 1x sight, it happens regardless of ADS or not if you leave the RAPTAR enabled on the other weapon.
Putting the RAPTAR on both weapons will prevent this bug from occurring to begin with based on my testing, regardless of whether they're enabled or not.
I'm guessing the FOV adjustments are applied on ADS, and the order in which the weapons are ADSed are screwing with the FOV adjustments when switching between different scopes.
Again, pretty benign since the odds of it happening is pretty low & the way to resolve the issue is pretty simple.