I should have explained a bit more. I'm looking for a pistol scope with AO for placement on a pellet rifle in the "scout" configuration (which needs a long eye relief (>20 inches). The AO is used routinely to determine exact distance from 7rds to 30 or more yards so that the pellet drop can be conpensated for. By the way, with a little work, an AO adjustable scope of modest mag. can also be used to judge distances out to 300 yrds for elk (or whatever) hunting.