I have a Glock 19 which I really like. Also have a Glock 32 and I'm thinking of getting a 40 cal. barrel for it. Then I saw advertisement for a 9mm barrel for Glock 32 or 23 and called Glock. They said you could use a 40 cal. barrel, but not a 9mm. Said it was not made to use the 9mm in. Doesn't make sense to me, but would like to hear from you. Has anyone tried it?