After reading the question several times, I feel mobow was wanting to know how do you determine your effective range, in other words your shooting abilities. We all know that with these weary animals your shot opportunities will differ with each shot.

You know, you have been practicing all year and you feel comfortable that (on the range)(non hunting situation)your abilities will allow you to take a shot X amount of yds. Ok what are your requirments for deciding that number right there for you.

For me if I can keep a 4" group consistantly, that is my effective range. (not in the woods obviously)
but before entering the woods I know I can shoot that far b/c I can keep 4" group at that yardage.

I think thats what he was getting at...Thats whatI got out of it!!!