On a Big bore--odds are you are hunting the big nasty's...and your shots will be less than 100 yards..elephant less than 50 --probably more like 25 or less...actually in many cases, your PH probably won't let you take a shot more than 100 yards...

Personally I have mine dead on at 100 yds..and shoot it again at 50 and 25 - just to make sure I know where it is hitting at those distances...

Ripp