The type of action and barrel contour can be a factor so if you could give more info it would be helpful as I'm sure others may have the same or similar setup and be able to help you.
I have a Leupold Mk4 6.5-20X50 on a rem 700 heavy barrel rifle with a 20moa base and used the low TPS rings. I had plenty of room for butler creek scope caps and still another 1/8" or so.
