Will Medium height rings work with a 40 mm Rifle Scope or can you get away with Low?

[KnightExtreme]

Wondering what height Rings would be required for a 40 mm Rifle Scope, medium or low? Trying to help select the right 1's for a friend as we rarely buy new rifle scopes which his GF is looking to buy with the rings with the right height rings as a Xmas Gift?
KE

 

[Macintosh]

Depends entirely on what its going on, but for a bolt action with a factory stock low would be normal height for a 40-42mm scope. I’ve even used extra lows a couple times. Mediums will be too high on most factory stocks.