[Tony Williams]

From ' Flying Guns – World War 2: Development of Aircraft Guns, Ammunition and Installations 1933-45' (details on my website):

"The first raid in Schweinfurt was a dramatic moment in the war in the air, but it did not stand out alone. Broadly similar results followed earlier and later attacks on targets in Germany. And on 14 October the 8th AF made a second attempt to destroy the ball-bearing industry; this time it cost 65 bombers out of a force of 294, plus 12 damaged beyond repair and 121 damaged. Only 62 bombers were not or only lightly damaged. The initial claim of the destruction of 288 German fighters, was later reduced to 104 destroyed, 26 probably destroyed and 17 damaged; but the actual German losses were 35."

and:

"On combat operations, the American bombers in the ETO expended 26.3 million rounds of .50" ammunition in 1943, and 36.2 million in 1944; the wartime total was 72.3 million rounds. (In October 1943, the ammunition consumption reached a peak of 632,773 rounds per operational day.) That corresponds to nearly 12,000 rounds for every enemy aircraft claimed shot down by the bombers. Because, as we have seen above, these claims were often far higher than the actual German losses, a more realistic average would probably exceed 40,000 rounds for every destroyed German fighter."

Tony Williams: Military gun and ammunition website and discussion forum