I am hoping one of the gurus here (thinking maybe you Dane, as you have done this with Kimbers I think) can help me with a project. I have a 40S&W gun that I have rechambered to 10mm. I is working well and is very accurate, I have just one issue. When I inspect the fired brass there is a slight ring near the end of the brass. From what I can tell the chamber of the gun (HK) might be a looser chamber than the reamer makes (clymer). In other words the extension of the chamber (the part that I reamed) is slightly undersized as compared to the original portion. When the round fires the brass expands more in the .40S&W portion of the chamber than the new, longer 10mm portion. How can I make it all match in dimension?