I just bought myself an XDm 4.5 40S&W, but I am looking to get a 9mm conversion barrel for cheap shooting/lighter recoil for practice and friends to shoot. I figured as long as I am buying an aftermarket barrel, I may as well get it threaded so that I can put a compensator or can on it in the future if I chose. Problem is, I have no experience with barrel threading and I don't know which thread is the "standard". I just want to thread it with something for maximum compatibility down the road. Any ideas?