OzFclass

Has anyone ever found that for a given powder charge, that a different seating depth performs better at long range?

i.e. Punching nice scores out to 5-600 but the long 8-1000 open up, .020" deeper in seating a the group flattens out again.

Am I going crazy, or is there some merit in this.

Jason, by varying the seating depth you can alter the ratio of vertical or horizontal movements in the barrel so your group shape alters because it alters frequencies, nodes- the lot including velocities with distance and the pulses from aerodynamic interaction. If you know what to map in testing the answer will greet you. Each barrel has its own personality.