Check out this article about the various new PDWs and 556 subcarbines.
I've heard the mk262 77(?) grain round is good for these kinds of weapons if you are looking to maintain as much velocity/fragmentation as possible with the shorter barrel. Does anyone have any more concrete info on just how much reliable fragmentation you can get out of one of these subcarbines, at what ranges, etc? How good are they versus 14.5 or longer versions?
Is there any other ammo loading that would give you equivalent fragmentation as the 14.5 version out to 50 yards? 100 yards? Do you need to special load some rounds with more pressure, etc?
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