Project Appleseed

http://www.mil-rad.com/scope_ring_calculator

Thanks! Looks really useful.  I could have used this a few months ago when I was installing a 50mm objective scope on my bolt gun. I got lucky.

Thanks!

It looks as if that calculator assumes that the limiting factor for minimal scope ring height will always be the objective bell clearing the barrel. 

That is not always the case.   With some applications that require the ocular lens to be positioned well forward, such as shooting from a prone position, some scopes and mounting rails will require the ocular bell to be positioned above the rear portion of the rail.  On some variable magnification scope designs, the zoom adjustment ring will sit lower than any other portion of the scope.  In these cases, clearance of the rear portion of the scope above the rail is often the limiting factor.

That's neat! Thanks for sharing it.

Personally, I prefer the slower but more sure method of getting the scope first, then placing it on the rifle with stacked coins or washers to find the optimal height & front/rear placement. Once determined, I'll measure the height & find a set of rings of the appropriate dimensions. That tends to ensure I won't inadvertently wind up with the bolt handle whacking the ocular bell or something embarrassing like that.