I have a Glock 24 that I like, but I'm interested in making it more versatile. I know the easy change, swapping in a .357 Sig barrel, but in researching some of the other options I came on some interesting info on the Glockmeister site. Apparently the Glock 17 upper (and its variants) will fit and function on the 24/22 reciever. They recommend an extractor and mag change to make it work, but it interests me since I have lots of empty 9mm brass and nothing else to shoot it in. I've also seen reference to a 9mm conversion barrel for the 22/24. Has anyone out there converted a .40S&W Glock to shoot 9mm, and if so, how did you do it and how did it work? How hard is it to change an extractor on a Glock? Appreciate any info - just doing a little gun dreaming while deployed with the USAF.