Low irons are killing me. HELP

I just purchase burner 2.0s.  I can hit the AW through the 7 iron pretty consistently, but i'm mishitting or topping my 4,5, and 6 at least 70 percent of the time.  Im 6'4" and i got a standard set because i was hitting the 7 iron so well and straight on the virtual hitting machine at golfsmith.  I'm about a 25 handicap.  Any suggestions or drills would be greatly appreciated.

Factors which influence how well you hit your long(er) irons:

• Clubhead speed. If you have lower clubhead speed, this makes it difficult to get them airborne. Also, heavier shafts have lower CH speed than lighter shafts.
• Shaft characteristics. If your staff is too stiff, or has a high kickpoint ( = low launch), it can be difficult to get high enough launch angle on longer shafts.
• Swing form. The longer the shaft, the smoother your swing needs to be. If you are trying to hit the ball too hard, this can throw off your tempo and where your club bottoms out.
• Looking up. If you are anxious about longer irons, your may have a tendency to look up on the shots, or move your head to "hit it harder" (see swing form above).

Some classic long(er) iron drills.

• High-low: Hit three smooth 9 iron shots; follow up with three smooth 6-iron shots. Then, alternate 8i and 5i shots, then 7i and 4i shots. Idea is to treat long(er) irons like the friendlier clubs.
• Half swings: Tee up the ball a quarter-inch, and hit some half swing shots with 4i, 5i. Get used to feeling impact of clubface on ball.
• Follow-through. Put a tee in the ground where you would normally line up your 4i or 5i. Address imaginary ball (on tee) with your club, and step through and up to a followthrough. Do not take a backswing, just step into the followthrough. This helps improve balance (so I'm told).

If none of this works, take a lesson. A good pro can find critical little things that us mid-HDCP players miss in our self-diagnosis.

With the 7 or 6 iron take your back swing only hip high and see if you make solid contact with the ball, only focusing on solid contact and not distance, if you top this shot you can break down your back swing.  usually if you top your irons that mean that you are not taking the club back on the correct backswing.  I like to pick the club up naturally with the guide of my left hand.

Imagine a circle and the ball in relations to the circle is slightly in front of the bottom of the arc and your backswing needs to stay within the circle so the bottom of your swing will make solid contact with the ball.

This drill has help my iron game.  also as a note, many players only play up to a 5 or 6 iron and play hybrids because it is easy to get your ball up in the air including myself.  you can still make solid contact with these irons but your ball flight is not ideal vs hybrids.

A possible cause is that you take the club back too far inside, and returning it along the same path. That means you are coming into the ball with the club on a very low trajectory, making it hard for the ball to get into the air.

If that is the case, then take the club back straighter, which will allow you to return the club to the ball on a steeper angle. That will help.

With longer irons (e.g. 4, 5, 6) would it be a good idea to choke up or have them shortened? You wouldn't lose any loft and it seems to me that a lighter/shorter club may be more manageable. I built my own driver (bought a G10 head and shaft separate) and had Golf Galaxy shorten the shaft so it plays around 44". I get more distance and accuracy w/ the shorter driver than I did w/ a stock TM Burner that came with a 46" shaft. Just thinking out loud...

Thanks for the responses. I will try these drills out.  I actually went to the driving range last night.  What i did was set up to the ball and then take 2 to 3 practice swings inside of the ball focusing on the bottom of my swing arc being slightly before the ball and allso make sure that i was keeping the club head low when i took it away and came through.  Then i just slid the club head forward and swung through.  It was the first time i hit this 4i, 5i, and 6i with any consistency.  Man did it feel good to crush that four iron finally.

Sounds like you've got it fixed.  I have the Burner 09's and had similar trouble.  I found that choking up a half inch really helped.  The Burners have longer shafts than most irons.

i'm going back to the dr tonight to make sure that it's fixed, i think what i did helped with a preshot routine, but my longer irons are usually the last part of my game to fall into place.  Thats not including a fairway 3 wood which i have never hit consistently.  Once i get my swing to feel good and consistent with my low irons, then i'll try to tackle that demon.