A Leupold base for the A7, if made, would certainly not be the same as other Sako ones, as Sako makes rings for most all their other rifle models and this particular model has an integral Weaver type base, needing ONLY rings to mount a scope. There are, of course, Sako rings made to fit this type of base, being Sako Weaver type rings.
Leupold's site shows no bases made to fit the integral base already there.
From your research, sounds like it may be so, but you should check out the Leupold website to make sure. The older model Sako's have a tapered groove for the ringmounts and I'm guessing they are the same way for modern Sako's. What the Tikka's have, I wouldn't know - they may come drilled/tapped for bases.
The Tikka also has a dovetail milled into the receiver. I don't know if it is the same as the Sako. The receiver is also drilled/tapped for bases. The ring mount supplied are not of good quality, escecially the metric screws supplied. I may try Tilley mounts for mine if I am sure they will fit.
The Tikka dovetail is a different width than the Sako unless they have changed something over the last few years that I'm not aware of. My Tikka which is a model 695 (pre Tikka T3) is also tapped so you can use with the "ring mounts" or a standard ring/base set-up and I think the Sakos are too. I think what Bigslow is saying is that he wants to use a standard base ring combo and he is looking for a base that will match up with the tapped holes.
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