Ok I just went into their industry page over on AR15 COM. This question was asked and answered.That's what I was thinking too, everything is supposed to be interchangeable.
Now we're not sure...
So, due to the width of AK magazines a standard width AR upper will not work with their lowers.
KS47 uppers will be sold stripped to work with their lowers. The KS47 upper can work with milspec lowers though. A full line of parts will be available shortly for builds.
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