SJ explained what the proper height should be for individuals, follow his instructions to see how it pertains to your situation.

However as far as warne rings go,med rings will accept most scopes upto 44mm objective. I have a 44mm Zeiss with warne maxima Med rings/bases, Idon't feel their is enough room to move up in objective size. I'd guess high rings will be what you'll need for 50mm, warne or otherwise. However try giving Warne a call and they'll be able to tell you if a med ring would work for your setup.

Good Luck