Quote History I understood you to be defending the tabs in the side at the top. Maybe my recollection is wrong, but I have seen those on all Mk16 rails.
Are you talking about the “dovetails” in the integrated upper receiver group? If so, I would say you would never see those in a rail, as they would be useless without the matching upper receiver.
It is a nice design, but it is 100% dependent upon the user to accept and never change the rail or the upper. Or, have Geissele introduce a new line of “dovetailed upper receivers and rails.”
I think LaRue has done something similar with its upper and rail combo, which makes it impossible to ever change. I like LaRue””’s .308 upper, fir example. But I cannot attach a Knights rail to it, as the connection is a bolt together integration, so you don’t get the upper without the rail.