Rifle Barrel “Break-in”

by Fr. Frog

This is another topic of great controversy! Very elaborate procedures have been put forth by many folks for the so called “breaking in” of a new barrel, ranging from lapping the barrel with polishing compounds before use, to shoot one/clean for the first 20 to 50 rounds, or shoot one/clean, shoot two/clean, shoot three/clean, etc. It is claimed that these procedures help to smooth the bore’s surface by allowing the surface of the bore to be smoothed without getting the pores of the steel filled with copper residue. This contributes to easier future cleaning and slower fouling. However, whether or how much these procedures are needed depends upon the original smoothness of the barrel. I have shot several rifles with extremely smooth (hammer forged) barrels that without any special breaking in, that have exhibited less copper fouling and were easier to clean than barrels broken it with complicated procedures.

The procedure most often recommended with a new barrel is to clean the bore with bore cleaning solvent and a cooper solvent as above. Then fire one round and clean the bore with a copper removing solvent - not with just regular bore cleaner. Fire another round and clean with copper solvent. Repeat this process until you don’t see indications of copper on the patch - this usually take 10 to 15 shots. Some people then continue with a shoot 1, clean; shoot 2, clean; shoot 3, clean; up to to 10 or 15 rounds The bore should then be significantly smoother, easier to clean, and less prone to foul. If you continue to see copper after 10 to 20 shots with this routine it may be necessary to have the bore lapped (unless you are very patient).

As far as accuracy goes, as with cleaning methods I have never seen any documented scientific data that any such breaking in has any better practical effect on accuracy or the life of a barrel than just shooting and cleaning using normal cleaning procedures. For the bench rest shooter with an extremely high tolerance finely made barrel, where hundredths of a inch can make or break a match there may be some slight accuracy advantages to special break in procedures. But for everybody else, extremely complicated procedures are probably a waste of time. But if it gives you confidence use whatever break in procedure you feel comfortable with. However, if the barrel is very rough, manually lapping or “fire lapping” (the firing of abrasive coated bullets) the bore to remove machining marks makes some sense. Most folks I know simply clean a new barrel before firing to remove any preservatives and oil and then again after the first 20 or so rounds. Then they go to their normal, after shooting routine. Just don’t engage in rapid fire (generally good advice) until you’ve put some rounds through the bore.

from Fr. Frog’s Pad