Gunsmithing having a barrel fitted to slide???

[unforgiven1]

im contemplating sending my xdm 45 to S.A and having the barrel fitted to the slide to improve accuracy, i cant find any info on how this is done and if its worth the money to have done.any thoughts?

 

[RMPSTRAT]

Re: having a barrel fitted to slide???

the barrel will be oversized in the forward of the chamber where it meets the forward edge of the ejection port and the bottom foot will be oversize at the foot