603 country, what combo shot all into one hole? I don't remember that.
If you're referring to:
The most interesting group was from the Lee Collet die. Of the 15 rounds, 9 went into one big hole. The other 6 were spaced out around the big ragged hole. So the full group was bigger than the smallest group of the day (Redding FL Die), but the Lee Collet die let me put 9 bullets in one hole.
. . .that's not all shots in one hole. 9 were clustered quite well but 6 were outliers that have to be included for that load's performance.
Had the cluster of 9 all been shot in a row, they might mean something good. Otherwise, I don't think it's a good idea to use them alone.
But you're making pretty good effort to find out what's best.