I saw one of the "Limbsaver Rifle Barrel De-resonaters" at a shooting supply store the other day and although I was intruiged, I thought I'd check of the forum here first to see if anyone has any experience with one of these. It looks like a small rubber dougnut - and talk about expensive!! $26.99! The claim is that the device (when slid on to the correct position on the barrel) "calms" the harmonics. How much "calming" effect could a little piece of rubber possibly have on a 30" heavy varmint barrel? What do you think?...fact or fiction?