Hello,

I have an old Ruger M77 in 22-250 caliber that I am wanting to replace the scope on; it has a bull barrel. I have purchased a new Vortex Viper rifle scope in 4-16 power with a 44 mm objective lens end. What model rings will fit the factory machined mount(s) on my receiver and what height is recommended for the scope I have chosen? The old scope was a Redfield wideview that was only a 1" tube. The one piece rings/bases were mounted with just one screw through the side of the base. Sort of like a quick removable model.

Thank you,
Tim

Tim here is an easy way to determine which rings will work with your scope and rifle combination using a grade school ruler.
Measure the heights of the ring base and ring itself then add them together. Subtract half of outside dimension of the objective. You're looking for a positive value. If you get a negative value then go up to the next taller ring. You can usually find the dimensions for the bases, rings and objective diameter on the manufacturers website.

[rail height + ring height] - [bell diameter x 0.5]
If the value is positive, then your bell will clear the barrel. You want to keep the scope as low as possible so you can maintain a good cheek weld.

Even with a 44mm objective I bet you can use low rings as long as the barrel is a 6 contour or smaller.

I always order the size I think I need and one higher. I send the one back I don't use
Make sure your seller will take back.

Picatiney rail and lows should work fine. That's what I have for my 50mm scope, but remember not all scope rails and rings are equal height.

44mm isn't that big, I bet mediums would be plenty. If you have the chance I vote for BIL's method above, order both and send one back.

Thank you guys. I am in fact using Brother-in-law's method.
Should get a visit from the brown truck mid-week. Just in time to have a bit of fun between hunts next weekend.

Tim