To obtain the best accuracy from your new McGowen Precision Barrel we recommend that it is properly broken in. The procedures outlined below are our recommendations and not “set-in-stone” procedures, we have found that there are a wide variety of break in procedures available out there and one may fit
you better than others. To get the most out of your barrel and ensure that it won’t foul in the future please use these or your ideal break in procedures.

There are 2 types of fouling that will affect your accuracy, copper fouling which is caused by the jacket from your bullets being stripped off in the barrel and powder fouling. Typically the first few rounds shot through your rifle will cause copper fouling. It is very important in order to prevent the fouling from
building up in your barrel to remove this fouling after each shot. Powder fouling is normal with any rifle or pistol and is easy to remove.

DO NOT USE MOLY COATED BULLETS DURING BREAK IN

  • We have found with experience that for you to get the best results out of your barrel that you should clean after each shot for the first 10 rounds or until the copper fouling stops. With all of our barrels being honed and hand-lapped we have found that fouling is minimal.
  • Always use a bore guide and a good, coated rod when cleaning.
  • Use good quality phosphor bronze brushes.
  • Use good quality cotton flannel patches.
  • Use a quality bore cleaner like Butches Bore Shine or Sweets to remove any copper. Copper residue will show up as blue with these cleaners.
  • Soak your cotton patch in your bore cleaner and swab through the barrel. Once the barrel has been completely coated let sit for 30 seconds and use your phosphor bronze brush dipped in the same solution and scrub your bore (about 10 to 20 strokes)
  • Afterwards, run a clean patch through your bore until it shows no signs of copper. You may have to repeat steps 5 through 7 until it is clean.
  • Use a good bore cleaner (not a copper remover) to clean the bore completely of the copper remover afterwards.
  • After you have cleaned after each shot you will be able to tell when your bore is no longer
    copper fouling. Once you have seen this you can move on to cleaning after every 3 to 5 shot group. This should be done for the next 40 rounds.
  • After which it is probably wise for you to check your barrel after each day of shooting or at least every 25 rounds.


Download PDF Instructions Here