Tuning for Positive Compensation (making different velocity bullets hit at the same vertical plane by altering the frequency in which the barrel vibrates – using the tuner weight).
This method of tuning should be conducted using a recoiling test-bench, shooting normally from the shoulder, or from a shooting bench rest.
- Select two batches of ammo from the same manufacturing year with at least 35 fps difference in velocity (e.g 1080 and 1040 fps).
- Make sure that the tuning weight is all the way backwards for the beginning of the tuning process.
- Shoot a few shots of the higher velocity ammo, following by a few shots of the low velocity ammo. If there is a vertical difference in the hits between the ammo batches, rotate the tuning weight forward one full rotation. Repeat this step until there is no vertical stringing. That is your “sweet spot.”
- *If you do not have two batches with a velocity difference, shoot 5 shot groups and move the tuner one full rotation each time until you have a round group with minimal vertical dispersion.
- For fine tuning – move the tuner in small increments. Use the markings on the tube.