i shoot the 4.5 storm lake 9mm conversion barrel out of my 40cal xdm 3.8 with no problems. I have a guy that said he would cut it down and recrown it for $35 but never gotten around to it and the extra length is not a problem. I just use it to be able to shoot more since it is cheaper then the 40 ammo.
Since SA will not sell either the barrel or slide as a part (only replace as a warranty item) you will have to go to an aftermerket barrel maker. This question would be best addressed directly to them individually as different mfgs will have slightly different designs. So some may work where others may not.
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