Just by looking at Jack's MX15 POI it appears to be closer to 3-4" high at 13yds. (How am I doing here Jack?) This would make the gun shoot about 9-10" high at 40yds giving him a shooter that patterns a little over 80% high at that yardage. We all have a different POA to get the POI we want at yardage depending on the gun we are shooting and how it fits us. Jack's MX15 has the same POI that I look for when setting up a new gun for myself. The most inportant, and basic, thing to consider when doing this is to FIRST go to the 16 yard line and start shooting straight away targets from post 3, raising, or lowering, your comb, until you are totally smoking the targets, regardless of what you see when looking down the rib. Once you are smoking all the 16 yard straight away targets, move to post 1, fire 5 shots, and watch your breaks. If you are not smoking those targets, make very minor adjustments to your comb until you are. Then move to post 5 and repeat. When done, return to post 3 and smoke those targets. Only after you have done this, and are comfortable with the results, should you do the same test that Jack did. Trying to determine POA just by setting your POI will not work for you until you determine where your individual POA is after you have done this..... Just my experience.... Dan Thome (Trap2)