Bottom line is some barrels might need 20+ rounds to foul to consistency. Which like most said, leave it alone once it settles down with accuracy. Just have fun and shoot it then.
IF, I had to Shoot 20 Round's thru My Tikka Hunting Rifles to FOUL and get GOOD, POI "Cold Bore", shots,.. I'd,.. Wrap them, around a Tree !
Clean,.. then, 2 TWO, Three Max, Fouling shots, "Get it Done" in My, carefully, "Broke in",.. Tikka, Rifles.
I ALWAYS Hunt with, a Fouled, Dirty Barrel !
Then, I Clean them, at around, 80 to 100, Fired shots.
I'm Finding that, My FIRST shot after, a Cleaning is usually about,. 3/8 th's to, a 1/2 inch, away from, the Next, 5 shots.
Maybe I'm just Lucky, But I HAVE, 3 Tikka's and all of them, are, doing,.. THIS !