southtexas,
Based on my experience you left the questioner hanging. I discovered from experimentation even a 1/16 of a turn will make a difference once you get close to the correct spot.
Is this your experience?
The 1/4 turn technique got me to 1/2" to 5/8". Fine tuning may have improved the groups even more. But that accuracy level from a sporting rifle was sufficient for me.
