How to properly break in a new rifle barrel

Breaking in a new rifle barrel can be easier than you think. 

"Is it necessary to break in a new rifle barrel? If so, how is it done? It seems confusing; is it important to follow the procedure exactly? Can doing it incorrectly ruin a new rifle? Help me, I'm so confused!"

I get a letter like that about once a month.

You may have read about the elaborate break-in procedures for rifle barrels that some gun writers are promoting. A few have come up with rigid schedules that they insist must be followed or you'll risk ruining the barrel.

It all sounds mysterious and a little scary for somebody who has just laid out a bunch of cash for a new rifle.

It's not rocket science

Relax, it's not that complicated, and it's hard to screw up.

If you are properly caring for your rifle, you are probably close to doing it already. In the end, all you are doing in breaking in a rifle bore is using the bullets you are firing to burnish any minor imperfections in the rifling.

Because those imperfections will collect metal fouling from the bullet jacket and "fill in," you must clean the fouling often and completely from the bore, particularly when the gun is new.

If too many shots are fired between cleanings, the fouling can build up to the point where it will be difficult to completely remove.

Removing the fouling after every couple of shots when the gun is new allows the next few bullets to burnish and polish the imperfections a little more before they start to fill in again.

If the process is repeated often enough, the bore becomes "broken in" because it's smoother and the inevitable tool marks and other imperfections of the manufacturing process have been removed or reduced.

So how long do you continue?

The rules aren't rigid, but the guidelines I loosely follow require that the bore be completely cleaned every two or three shots for the first 20 rounds fired through the rifle, then cleaned every five shots for the next 50 shots. After that, I clean as often as necessary.

"As often as necessary" means that the rifle should be cleaned before it's put away every time it is used. During use, it means to clean the rifle whenever accuracy starts to deteriorate or every 20 or so shots, whichever comes first.

Every time the bore is cleaned, it continues the break-in process. Regardless of how you do it, the key is to completely remove all fouling each time and to do it often enough that the fouling doesn't have a chance to build up.

Bullet-metal fouling is detrimental to accuracy in any rifle barrel. It also is a potential location for the beginnings of corrosion, which can pit and ruin a bore.

Anything you can do to reduce fouling will be beneficial to the long-term accuracy and life of the rifle.

The process is progressive: Each time you clean a barrel, the subsequent bullets gradually smooth any minor imperfections left in the bore, leaving it a little smoother, a little better, a little more accurate.

That doesn't mean that you can make a bad barrel win benchrest matches, but any barrel will benefit from this treatment.

This article was provided courtesy of the North American Hunting Club, North America's largest and most dynamic group of avid hunters. Click here for a free trial membership in the Club and a free copy of the members-only magazine, North American Hunter.