Eddybo , tuning barrel has been around for a long time the rimfire BR guys have always been into it by way of everything from extravagant precision machined micrometer adjustable ends to wand of rubber bands , I have see guys trim their barrel .050" at a time to try to get a barrel to shoot a load that showed very low ES numbers with realy high velocity , and it did show that the accuracy was affected as the groups both grew and shrunk. Its the same basic idea that Browning uses and its a great idea for guys that don't reload and thats tune the barrel to match the harmonics that the specified load is creating.
This subject has been attacked from many differant ways , from adjustable pressure points in the forend for barrel pressure , adjustable tensioned barrels , guns with fully glued in barrels , barrels bedded with silicone , adjustable nodes on the barrel or in several differant spots , its a vary widely looked at subject and somebody somewhere along the line might stumble accross somthing that will chance target shooting forever , but for the time being look at the guys that hold world records and the tools that they use talk to the "guy" that have been inducted into the BR hall of fame ;) and see what his ideas on it are (though I still can't get my head around his methods and the success he has with them)
But the main thing is if we were content with what got us by we would still be throwing rocks !! so if you think you have an idea then put it to work and test it out never now you could be the next Eddison , Columbus , Magelin or anybody else that changed the world with some crack pot hair brained idea
just a note ,keep your figers and all loose objects away from the lathe chuck , I wacked the piss out of my thumb today and remeber always wear your safety glasses.