Yeah the threading on the MSR Barrel is 16mm I think? Its pretty big.... Definitely not 14mm. Also the barrel doesnt end in a thread if that makes sense. The silencer has to have the the extra bit so it can screw into the end of the MSR barrel.
If you can see in this pic. The silencer has a small bit on the end. That peice has the threading on it. That then screws into the outer barrel of the MSR. I had to build up the thread of the silencer with tape so that it fit the very wide thread of the MSR. I then ran a tube down the center that rested on the extra bit of inner barrel. You have to do this as the silencer doesnt sit exactly center without it and bbs with smash into the inside of the silencer when shooting.
Ill try take a pic of it for you tomorrow. Its night time here now.