You can get a new barrel for a .40 S&W to make it a .357 Sig, and use the .40 mags (.357 Sig is a .40 case necked down for a 9mm bullet, I believe). You could theoretically put a 9mm barrel on a XD .40 and get 9mm mags (not sure about the recoil spring weight). With my XDm 40 I could get a 9mm barrel and mags, but only because I know the XDm 9 uses the same recoil spring (18 lbs). I've read about several .357 Sig conversions, but not many 9mm conversions.
I see your xd, do you have a holster that can hold the xd with a light? Where is the best place to get one?
I shoulda got one too, but I didnt want to stand next to you and look like the bopsy twins...I got a UTG drop leg holster at the 1500 for $20. It fits my xd9 with light perfectly. Also has an open bottom so can accomodate 5 inch barrels.
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