Ok, so if you've done your work as said, it should be closer... but don't jump to conclusions. Different guns shoot different and scope height plays a part.
There is a reason why experienced shooters say do it in the real world... because like myself, they probably can't tell you why it's not correlating without looking at it or even shooting it... but it doesn't matter. What counts is when you dial for 55 it hits level, and when you dial for 35 it hits level... doesn't matter a jot what CG says it should be unless you will happily hand over the points you gain when CG says you should have missed.
Did you check it at 30 yds as well on paper so you know you aren't 10 clicks out at that distance? It's a very small amount at that range and if you aren't punching them through the same hole at that distance your error is covering the possible adjustment needed.