I climb into a helicopter that has a ramp, e.g. the Huron. (I'm a sniper)
I sit on the rear left seat (the seat which has control of the ramp).
I have a laser designator in my weapon list.
Then I open the ramp of the choper myself (not the pilot) to look outward through the open ramp.
If the pilot closes the ramp and I am still watching through the laser designator, then it happens a bug.
My weapons switch automatically between the laser designator and for example my snipe without ending as if I was scrolling between weapons and selecte each weapon after the other.

I don't know if it is only the case for the sniper or for other soldiers.
I don't know if the zoom or the night mode of the laser designator has an influence on the result.
I don't know if it's happen for each choper.
I think that if I close the ramp myself, it does not happen.