Just happen to be in combat trying to aim doesn the sights with scope or just being close an attempt to fire a weapon.
Linking 3 exhamples
https://plays.tv/video/5baaa9bd2dff0d9fe7/killing-with-lag-in-balota
https://plays.tv/s/LurWmF1DI3A8
https://plays.tv/s/LurWqeV1wxON
As ou can imagine from the videos it can be very frustrating.