Forward-fixed helicopter mounted cannons are currently almost unusable.
This is because the convergence of the rounds is at almost 1.5 kilometers, far far outside the typical range of engagement for a light attack helicopter strafing infantry.
Additionally, at this distance, the rounds have less than 25% of their muzzle velocity remaining, rendering them much less effective than they would be at say, 700 - 200 meters (approximately the range of engagement using such a weapon).
Because the guns are zeroed to very long range, the pilot typically winds up shooting on either side of the target, leaving it safely between the guns lines of fire.
This issue is only made worse when in the Wy-55, as its cannons sit significantly farther apart.
Either the cannons could be permanently configured to fire at a shorter distance, or could have two settings, one for 300m and one for 500m or similar distances.
These settings could also change the reticule distance, as the cannon's convergence and pipper do not point to the same range.