Mike Ezel may make the most advanced tuner on the market. I dialed my 6 XC, 6 Dasher, and 6 BRX to shooting in the zero's and 1's, best shooting I have ever done in my life! I have a RAS Tuner/Brake on another 6 XC, and it also shoots in the zero's and 1's. It really makes you stand up and shout when you are shooting 3/8" at 300 yards in good conditions.
I want to put a EC tuner on a new 280 AI.
Years ago, I was shooting thousands of p. dogs a year, and went to unturned blanks to reduce recoil. I made a SS collar that was 1/2" in thickness and put it on the barrel with three opposing nylon-tipped set screws. The collar would slide up and down on the barrel with only .002-.003 clearance. I could make slight adjustments and groups would open up or close up. I started off with the collar just in front of the forearm tip, and started working out, never having to go too far out...most of the time. '
An engineer friend was hunting dogs with me, saw the collar on the barrelS, he went and patented the Browning boss system. He was Rockwells' #1 engineer. He also invented the 17 hmr after being involved with the development of the Federal Gold medal match ammo, and building the 22 RF Olympic rifles that whooped the Russians!
I have never got into the physics of the harmonics, I just screw them to the rear, and start shooting two shot groups. I never make over two graduations at a time adjustments, shooting two shot groups. There are always more than one setting that will shoot small groups, but you want the setting with the widest spread over 4-6 graduations. That is as far as I get in the tuner technology, they just work, simple and quick the vast majority of the time.
Guys really screw up when they start adjusting half a revolution at a time on the tuner, and this leads to much frustration.