Assault rifles and their ammunition

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Yikes, that chart on p. 29 seems to make a pretty good argument for the 5.56 cartridge. If you figure the Grendel weight as similar to a 7.62x39 round then you are only buying another 30 seconds over the 7.62 NATO, whereas the 5.56 buys you 3.5 minutes....

Too bad the 5.7 round isn't available with base bleed technology and a micro nuclear payload. I'd be real happy with a P90 if it did.LOL