.40S&W to 9mm
Not only the Shield, but my XDs, Glocks, Sigs and M&Ps which are in .40S&W, all are
in the three barrel flavor........40S&W, 357Sig and 9mm. The secret is that the 9mm barrel must be of the 'bull barrel' size. All of mine function flawlessly. The 9mm mag
must be used with 9mm...