I see that you have taken photos only from the right side of the gun..... What the devil have you done to the left side since you won't show it to us!!
Thats exactly what I was just talking about doing about a week or so ago! The shorter inner barrel inside the standard outer barrel.. So it does sound quieter that way?? I have been debating it for about a month,lol..I just use the 430mm inner barrel in the 690mm outer. It works fine. I was going to use a normal lengthed outer barrel and a suppressor but the longer outer barrel works as a suppressor too so I'm not going to trouble PDI by having them pay for posting to and from Japan just so I can swap barrels.