How to aim from RP-74 (PKM)? (STALKER: Call of Pripyat)

I am aware that this cannot be done in the original, which is rather illogical, because the machine gun has sights. I downloaded the corrected w_pkm file, including from this site, but the machine gun disappears from the screen when you press the right mouse button. Then he himself changed the value in the line responsible for aimed shooting, but the result was again unsatisfactory - the disappearance of the machine gun after pressing the right mouse button.
So how can this be done? Give me good advice, I will be very grateful! Monique 16:9, if that makes any difference.