stormshadow,
How much adjustment right or left did you need to make when you used the Talley's ?
If it not very much then you would need to shim the base. You can go to a hobby shop and get a package of brass for a couple dollars and make your own shims.
When I mount a scope I make sure the cross hairs are mechanically centered on the scope then I mount it. Then shim the bases to center the cross hairs to no more than 2 MOA adjustment with the scope. You want to have the cross hairs is close to centered in the scope mechanically. Because it can cause accuracy problems at long distances.
I have a Winchester Model 70 pre-64 257 Roberts that had the same problem shims solved it. Having mounted several thousand scopes I have come across extreme problems only 3 times, all were solved with shims.
