BudsGunShop.com - scope ring size

Thomas, One inch Rings are shipped with this rifle.

I FOUND IT it come with 1 in rings "Ruger's patented integral scope mounts are machined directly into the stainless-steel receiver.***** A matching set of 1-inch, stainless-steel rings are shipped with the rifle*******. This mounting system eliminates the need for a set of base screws that could loosen and fall out in the field and it does not interfere with the iron sights"

I think that they are 1 inch rings however I cant find it in writing so I suggest that you call ruger to be 100% sure Telephone: 336-949-5200 / Fax: 603-863-6165
(Monday through Friday 8:00am - 5:00pm ET)