I'm guessing they are proprietary. I never tried a 700 base, but they have 5 holes for the bases.
They are proprietary. The diameter of the receiver is much smaller than a 700. The screw holes are also the larger/stronger 8-40 size.
The three mounting holes in the front are not all used when mounting the front ring. You only use two. The three holes are there to give you more flexibility to position the front ring in the best spot depending on the length of the scope tube forward of the turrets. You can flip the Talley mount either direction and place forward or aft on the three hole pattern.
