If the "tuner" (harmonic balancer) is working properly, it still might take a while to get it in sync with your gun barrel but one would have to stick with one brand of ammo and the same bullet weight for it to be anywhere near consistent. Hand loading will do the same thing. Find the load your barrel likes and stick with that load. The beauty of a harmonic balancer is that you can find the sweet spot for a load, note the setting and then find the sweet spot for different load and dial-in loads based on previous experimentation (assuming everything is working correctly)! I you start out close up (50 yds. or so) it makes it easier to tune it and then progress out to longer distances. Theoretically, the scope will only tell you where your group will hit, not necessarily close up your group (if the shooter does a good job).