USP 9/40/357 swap?

[hobbyist]

Guys,

I have a USP9 that I dearly love.  I use it for home defense and sometimes for concealed carry, although my standard CC weapon is a Sig 239/40 normally.

I am thinking about buying a 40S&W barrel for the USP.  I know that I will need a 40SW magazine, but anyone knows if I can swap barrels like that?  Anything else needs to be swapped?

Thanks for your help in advance.

[Mikey]

hobbyist - a USP chambered for either the 40 S&W or the 357 Sig can interchange those two caliber barrels with only a barrel change.  Not so if you have a 9mm now - that is sort of like a fixed caliber.  If you can find a 9x23 or 38 Super barrel for that 9mm, if it is one of those that will handle the longer cartridge, you can go that route.  Bit, if you want the 40/10mm/357 Sig interchangeability you have to start with a handgun in one of those calibers.  HTH.  Mikey.