My break in procedure is this, clean the barrel thoroughly before shooting it the first time. Shoot it till it's hot 20-30 rounds and clean it again while still warm. Repeat 2 more times. I have some very accurate rifles that don't string when hot either. If the barrel is rough inside it will show quickly with this treatment and it will get the lapping paste treatment after removing the copper fouling. I was doing this long before anyone came out with the shoot one shot and clean it again method, saw no reason to change my ways.

Dog I rescued in January

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