"Light machine guns are used to suppress the enemy and can
devastate an enemy squad when used in an ambush. They can be deployed to
greatly increase their accuracy and stability. When using the deployed LMG,
accuracy suffers less from shooting but a lot more from moving around. The
player's stance (standing, crouched or prone) does not affect accuracy while
the LMG is deployed." <- look what i found in the project reality manually
(although the game is not the same with fh2 the both have the same feature.