I will be interested to hear your thoughts on this. I had a number one in .220 Swift that was somewhat erradic,(POI climbing as it heated up), and Mark De Hass helped me fix it up. All we did was remove the presure lump in the front of the barrel channel and the drill and tap a 10x24 hole though the front end of the hanger bracket after removing the barrel nut. Then all you need then is an allen head set screw and matching wrench. I started with about a 1/4 turn of up pressure after the screw contacted the bottom of the barrel. I kept on tweeking it and shooting till I got it right on. If I remeber correctly, it took about a half a turn of pressure to get it right.
After we got it shooting it would hold amazing groups out to 350 yards. Moisture, heat, nor cold affected it after that.
I hope this device does as well for you. Have you ever tried one of the rubber barrel donuts that they have out now? I never have, but I would be interested to know if they really work or are just a gimmick. Bob H.