Home > Gunsmithing > Resources > barrel break in
The new barrel you are ready to "break in" has been thoroughly lapped by the barrel manufacturer to the finish that they deem the best. I don't subscribe to the repetitive shoot/clean methods, heres what I do, and what I recommend in general:

-mount your scope, load a few rounds, and start shooting with about 10-15 rounds to get the scope zeroed. Load development starts at shot #3 for me
-insert bore guide
-patch the barrel clean with whatever your common use solvent is, I use Butch's Bore Shine.
-brush the barrel with a bronze brush and the same solvent you've patched with, I usually brush15-20 strokes
-patch the barrel clean again, and inspect the bore at the muzzle end for visible signs of copper. If copper is present, use a copper solvent to remove copper
-brush again briefly if copper solvent was used, verify copper is gone
-patch out cleaning solvent, then run a patch with a fast drying solvent like brake cleaner. I then remove the bore guide, and finish with one clean, dry patch. Swabbing the chamber and neck, then patching out the barrel

I would now go shoot 15-30 more rounds and repeat the above. When copper is not present after brushing, I consider the barrel "broken in". Note that Ive had barrels that will hold small amounts of copper for their entire life, I don't care about this as long as the barrel is shooting good. Visible copper is not necessarily a problem, but excessive copper buildup can lead to a problem. In general, I clean my barrels after my "batch" of ammo is used up, this is usually 35-50 rounds. I will always clean after a 100 or 200 round steel match as well