You are usually handed off prior to loosing VHF range. You'll get a primary HF and a back up freq. You can usually hear the VHF for awhile afterwards though. But, after the SELCAL checks good, I usually tune in 121.5 and 123.45 and enjoy the quiet.
As far as a specific chart, I haven't specifically looked. I will next time since my curiosity has been jabbed.
In telecommunication, slant range is the line-of-sight distance between two points which are not at the same level relative to a specific datum.
An example of slant range is the distance to an airborne radar target, e.g., an aircraft flying at high altitude with respect to that of the radar antenna. The slant range is the hypotenuse of the triangle represented by the altitude of the aircraft and the distance between the radar antenna and the aircraft's ground track (the point on the earth at which it is directly overhead). In the absence of altitude information, the aircraft location would be plotted farther from the antenna than its actual ground track. An easy formula to calculate a slant range is: 1.225*square of altitude(in feet)=slant range.
Using this formula should allow you to calculate line of sight reception from any given transmission facility or antenna.
time of day will have an effect of total range too with effects from the Ionosphere.
I was climbing out of PFN (panama city, fl) one early morning before sunrise...we were getting bleed over from some place in Oklahoma with the ctr freq we were on. We heard both parties...a/c and that atc controller. Wasn't clear as day, but good enough.