Originally Posted by Skibbo
That would work. Just a little piece shaped like the existing filler piece, but rounded to 1" OD on the top? Probably 3 holes so you could use CCI/CCM feedkecks (2 holes) and then 1 feed hole.
i think thats overkill
ease of machining says square bottom, radius top, big hole, or even a slot for screw clearance
the amount of effort to take the adapter out and put the stock vert feedneck back in isnt worth the extra ops to make the part for ccm/spyder feednecks