Do not take creditability in range balls. They are completely unreliable. Their flight characteristics are like a cannon ball -- they can be launched up and they travel far, but they do not maintain loft holding them in the air. They will fall quickly and you get your 6i = 3i results.

Test and gauge your distances with real golf balls. Test them on a real course late in the day when no one is behind you. Play some shots to designated targets and take the averages...then play a different club to the same points and take those averages...eventually you will get a good distribution to evaluate. (Be sure to fix all divots).

If you do this and you still see problems with lengths being to compact, I would turn to your equipment and have them tested. I had a 4i that was equal in face angle to my 3i, so it was bent to proper specs and that solved my problem. If your shafts are different, that can have the same affects...they might be slightly longer/shorter, stiffer/weaker, etc.

After that checks out, then you are safe to start to look at your swing.

Moving the ball forward helps maintain a sweeping angle of attack on the longer irons. You don't necessarily want to hit them high with a steep attack, so a forward position helps that.

What I see mostly as a cause to long irons going the same distances is the overall swing speed generated by the player. If this speed is significantly slower then normal, you do not get good compression on the ball, and you loose distance to flight/carry. The ball is struck with too low of a spin and it just bumps out there on a common trajectory.

The solution is to work on your swing to increase swing speeds while maintaining control. There will be a limit that a person's abilities will have, so at some point, you would exchange a 5i for a hybrid. And continue to replace the longer irons with these woods to help create the desired distance separations.

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I'm a golfaholic, no question about that. Counseling wouldn't help me. They'd have to put me in prison, and then I'd talk the warden into building a hole or two and teach him how to play. ~Lee Trevino