Gatt, I believe and support your assertion that the Italians had some 12.7mm rounds with explosive charges. The Japanese did too.
Realistically, the difference in damage would not be too much, in the game IMO.
FYI alot of the .50's that the US and the British used were incendiary rounds, that would have served much the same purpose, in the actual war. To ignite enemy aircraft combustibles. Fuel, oil, oxygen, etc.
I once got too visit a military munitions plant, and the plant engineer showed me alot of different types of ammunition, and we discussed what they did and why.
Basically a 20mm cannon round is much larger that a 12.7mm (.50 cal) MG round, and therefore can carry a significant payload of explosives, plus a fusing device.
A 12.7mm round can only carry a miniscule amount of explosive, and to be honest I can't remember how they even fused them, but I do remember that I was shown a cutaway version of one of these shell types.
So what effective would a 12.7mm explosive shell have in the game? Well, I'm not exactly sure to be honest. But dont' expect them to suddenly have the effect of a 20mm cannon.
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Vermillion
**MOL**, Men of Leisure
"Real Men fly Radials, Nancy Boys fly Spitfires"
[This message has been edited by Vermillion (edited 07-25-2000).]