I really don't think it's out of line at all. Remember, we're estimating 1700 f.p.s. You may be getting more than that.

If you look at the first chart on my last post, it says with a 15 yard zero you will be 2.3" high at 50 yards. On your target you were pretty much dead on at 15 yards and about 3.3" high at 50. I figure that's pretty close for a mathamatically calculated chart. Heck, holding the gun either tight or loose against the shoulder can make a one-inch difference in POI at 50 yards.