ridgerunner ky, I'm sure I remember it from a History class at some point, and although I don't have a copy of the Military's official report, it's pretty commonly known.

here's a link to the refrence of the theory at Military.com

Quote:
What it all boils down to is that when the 5.56mm cartridge was first introduced to U.S. combat rifles, it was adopted because of its size and its fit with the U.S. "shoot-to-wound" philosophy of the time. While the 7.62mm NATO round used in the M-14 is much more powerful than the 5.56mm bullet, it is also much larger; a soldier can carry twice as many 5.56mm bullets as he can 7.62mm. In extended combat operations (wars lasting years), it was also estimated that wounded combatants would require more logistical support than dead ones -- with this in mind, the U.S. adopted the 5.56 round, since if the bullet did not kill outright, it would certainly cause a serious enough injury that the casualty would be hospitalized for a significant amount of time.
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