Since you are referencing a factory rail I'm assuming you have a Mini-14 with the Amega rail up front in lie of the traditional hand guard. Yes, its a Picatinny spec rail which gives you a wide variety of rings to choose from. Most Weaver-style rings will also work fine on this rail.
The Amega rail is a forward position mounting platform thus traditional scopes will not work well there. Such rails are designed for use with red dot sights of various designs and scopes that feature an extended eye relief often referred to as Scout scopes. Some enthusiasts also mount pistol scopes on forward rails as they're light, built tough and also have long eye relief.
For a traditional rifle scope mounted in the more usual position over the bolt you'll use the Ruger supplied rings or aftermarket rings designed for the Ruger receivers. You'll observe two small scallops on each side of the receiver where the ring bases clamp to the receiver. This is the propriety Ruger system, for better or worse. The Warne Quick Detach Ruger-style rings are very popular for this application.
The supplied rings from Ruger should be 1" rings, simply measure the inside diameter to verify. 30mm rings would a diameter of approximately 1-1/4".
Ruger will exchange rings with you at no charge as long as they haven't been used. This allows you to change your ring diameter or ring height as needed for the particular scope you plan to use.
Another popular option to mount a traditional scope over the bolt is the use of a small Picatinny/Weaver style rail that mounts in the receiver scallops just like the Ruger rings do. Popular selections are the Weigand mount and the GG&G mount. Both are very similar in design and construction and cost is comparable. With these mounts in place one can then select the preferred Picatinny or Weaver style rings. Using mounts such as this will result in a higher scope position as compared to using Ruger style rings which may introduce cheek weld issues with the factory stock. A strap-on butt pack/cheek pad will usually resolve most cheek weld issues.
Hope this helps and good luck to you.
