I always sight-in for a MPBR system, BUT IT IS ALWAYS CALCULATED CONSERVATIVELY (CMPBR), to the tune of 1/2-3/4ths tgt. size!! In other words for the coyotes in my area of operation they avg. about 6" from top of back to bottom of brisket, skinned of course. This means that i usually have the "maximum ordinate' (highest point of trajectory) no more than 2" above line of sight, and the MPBR is calculated to be the distance that the bullet drops 2" below line of sight. That's the way i calculate and apply it.