I am awaiting receipt of a used Ruger M77 standard sporter rifle. In the mean time I wanted to purchase scope rings for it. I have a Redfield 3-9x scope that I plan to mount on it. The scope has a 50 mm objective and a 1" tube. The OD of the objective measures 2.25". I also have a Butler Creek dust cover on it. The OD of the dust cover installed is 2 3/8". What height rings should I use. Mediums are listed as .435 and high rings are .565. I would like to keep the scope as low as possible. There should be about .6875" extension below the scope tube. I do not know how high the ring mount base (on receiver) is above the top of the barrel surface or the rate of taper of the barrel. Anybody know the answer? Thanks, Peter.

It might come with Ruger rings that will work with that se-up?

Cheezywan

You'll need the high rings. Standard Ruger rings are for 40mm scopes and often won't even work on a 40mm with an adjustable objective.

Ruger will usually exchange the rings with you if you send in the ones that won't work.

Yup - when first buying my Ruger 77MkII in .223 Rem, wanted to mount a Burris 6x18x50 and the rings that came with it were too low. Called Ruger and explained and they swapped the rings out for a higher set.

If you can't get any results, let me know. I've got a half dozen or more sets of Ruger rings.