Ping g20 irons

[ThumbtackR9]

Seventy year old senior high handicapper.  I have made several post on different things.  I posted that I bought a used set of Ping g20 irons with the ping cfm regular shaft.  I finally got a chance to go to the course and hit a few today.  Just hit some balls.  The irons felt great hitting inside on the swing monitor off the carpet.  At the course it seems like everything goes straight up in the air and I don't  know how many balls I just flat shanked and I don't hardly ever do that.  I hit a 8,9 and pw.  I could barley get 90 to 100 yards out of the nine iron.  I have never had clubs that I get this much height out of but I am not getting any distance.  Is it just my swing or is it common for these clubs.  The clubs seem to have a lot of offset.  Could this matter.  I also have a set of Cobra Z Fly irons with A flex shafts.  It  seemed like I got a little more distance with them but not as much height.  Any comments.  

[ThumbtackR9]

Sorry I meant to put cfs Ping shaft.  I knew cfm didn't sound right.