9mm will work in a .40 mag...and i've had no problems with the extractor on the g22 with 9mm. The ejectors are different, but i have had no issues.
Just make sure you have the 9mm barrel on when shooting 9mm. I've seen guys put 9mm down the pipe on a .40.
Last edited by Gutpile; 11-28-2009 at 09:06 PM.