I'm using range balls at the range to gauge the distance.

10-13 yard gaps are fine, the problem is I'm not getting that gap as the club gets longer for my irons. So effectively from 6 -3i, I'm hitting all of them at around 185 to maybe 200 on the fly at best.

I'm curious to see if anyone can explain the logic of moving the ball forward yet still achieving the longer distances. Think of it this way, when I place my 7i in the middle of my stance, the loft angle appears to be exactly the same as my 6i one ball length to the left of center. So that to me makes sense as to why my 6 and my 7 seems to hit ~ the same yardage, given that I set up as indicated. So can someone explain this?