Originally posted by B@tfinkV
dumping ammo weight does help plane performance even if only in small fractions.
Losing 40lbs on a 10,000lb machine won't help you. If that were the case, Fw190 pilots would fire off 400 of their 20mm rounds, saving FAR more than the cowling MG weight would save them, and still allowing them enough ammo for many kills.
If that were the case, spit pilots would ONLY fly at 25% fuel, get 1 kill, and RTB for more fuel.
At a certain point, saving weight is useless.
Firing off the lesser guns to save weight is beyond useless, especially in the heavier planes.