Saw an old friend today and he was sighting in a new rifle. Gunsmith had installed a new barrel on a 700 receiver and it was nutless. Strange to me was it was a barrel bought from Remington. The owner said something about it being and "X pro barrel" or something like that. It had the Remington factory roll printing but eluded to the fact it was custom. Has anyone heard of this? Where do you get them? Do I want one?