I have medium leupolds on my fclass straight taper 60mm objective and have a solid 1/8" maybe more using a 20moa base. There is a good chance with a savage pencil barrel you can use lows.
I have a Nightforce NXS on it and honestly I wouldnt go any shorter. Its seems about perfect really. I called a tech support guy from the place I got them and thats what they had recommended.