Three basic problems may be encountered with mounting some modern scopes on the Win 70. I have overcome the issues with varying methods. Don't be afraid of mixing and matching and thinking outside the box about bases and rings. After all, you are the owner and user of the equipment. :) And if you have friendly, local gun store- use them. Many times I've been able to go behind the counter and sort through different odd parts and mounts, etc. to come up with what works.
As has been posted, the Win 70 has had the different hole spacing systems over the years and different set-ups for their "magnum length" scope mounting specs. You'll have to get out your calipers and determine which you have. Then as a FACT with the M70, the rear section of the receiver is lower than the front, so the rear base/mount HAS TO BE TALLER BY THE SAME AMOUNT. If not, cinching down the scope will put unwanted and damaging bend forces on the scope.
The final thing I've run into, not only with Win 70 but others as well, is that many modern scopes are "short coupled" which may not allow proper ring spacing/location on the scope for proper scope location on the rifle. That's where the mix and match and "thinking outside the box" may be very useful.
IMO, if you can figure out how to do it, one of the best and strongest systems that may allow optimal ring location on a short bodied scope on actions like the Mauser 98, Win 70, Montana 99, etc., is the dual dovetail system.
On a Mont 99 (very similar to a Win 70) I had to use a set of dovetail rings by one manufacturer, using the off-set on the front, then mate those rings to two different brands of dovetail bases to get where I needed to be on the rifle. I used a 1" lapping bar with compound to ensure perfect alignment between the rings and pesto! IMO, the best, strongest for my purpose.
Pics showing short scope mounting on Mont 99 using dual dovetail set up. Mounts don't impinge into port and scope is rotated 90 deg left for max scope/turret clearance for ejection and loading.
