BARREL life and breakin

Some people think a barrel should be "broken in" with some combination of shooting/cleaning for best accuracy. Others (including me) say it's unnecessary.

I been shooting center fire rifles for over 45 years. When I first heard about breaking in a rifle bore, I liked the idea. After trying it on 3 new barrels and thousands of rounds 223 and 22-250, I did not see any real benefit. Some shooting friends feel it helps them. More bores a ruined by bad cleaning then not cleaning IMHO. Your results may vary.

With the older methods of barrel making, rough barrel interiors, especially on the lands, was very common. This rough surface scraped metal off the bullets in a random manner, leaving fouling in the barrel and bullets with uneven surfaces, both contributing to inaccuracy.

While modern barrel making has eliminated many of those problems, many folks think that firing a certain number of rounds to smooth out ("break in") a barrel will bring out the best accuracy. It is not as hard and fast as some folks think, but often a barrel really will shoot better after firing some number of rounds. A rifle belonging to a "one round a year" deer hunter may never reach that point, but many folks prefer to fire some number of rounds (the iffy nature of the whole thing is shown by the wide variation in the recommended number of rounds) when the rifle is new, to get the benefit immediately. Another way to "break in" a barrel is to fire bullets with abrasive to "fire lap" the barrel by smoothing out any rough surfaces.

Obviously, if firing can smooth out a barrel, it will also wear a barrel, from the friction of the bullet and the hot gases from the burning powder. There can also be wear from other sources, like cleaning rods. At some point, the barrel wears or erodes to the point that the bullet will not be stabilized and accuracy will suffer. One major cause is throat erosion. When the powder in a cartridge begins to burn and turn to gas, the gas first expands the case neck. But the bullet, due to its own inertia, does not move immediately. Instead, hot gas rushes past the bullet and enters the barrel throat, where the rifling begins. That hot gas eats at the throat metal and the rifling and eventually erodes away the rifling. When that happens, the bullet will not enter the barrel straight, but will slew into the eroded area and distort before reaching good rifling. That will cause inaccuracy, and it is said the barrel is worn out.

Barrel life is expressed in the number of rounds fired between the barrel being new until its accurate life is used up. Depending on the caliber, and other factors, that can be from 3000 rounds to 10,000 rounds. Rapid fire and allowing a barrel to get very hot will reduce barrel life.

HTH

Taliv wrote: "...there's no relationship between barrel life and break in as far as i am aware..."

Well, there is. but not the way one might think. Every shot adds to barrel wear. If, on average, a barrel of x alloy in y caliber will last 5000 rounds, it will last 5000 rounds. If a shooter fires 1000 rounds into the backstop to "break in" the barrel, the usable barrel life will be 4000 rounds. Will the next 1000 rounds be more accurate than if they had been fired without "break in"? Ah, that is the question, isn't it?

Jim

I just shoot the gun....no hassle, and it always seems relatively the same.

Those that are heavy into compitition, or just want to get that last mm of accuracy will lapp their new barrels with extremely fine grit polishing compound, or will purchase lead bullets with the grit embedded in it.

My kit has 240, 340 and 600 grit. you can lapp by hand using a slightly oversized lead slug (molded in the barrel) and pushing it through by hand (best) You can litterly "feel" the imperfections using this method. You cantinue to lapp until it is absolutely smooth felling.

You can use the prepared lapping slugs, handload them with a light load of powder, then fire them.

Lapping probably improved my Rem 700 about 0.1" at 100 yards. I have a friend that did not get very much improvement to his rifle (don't remember the model) until he recut the crown. Just two things that can help take a 1 min barrel down to a .5 min barrel.

I don't put much stock in breakin periods, the last three savages and my tikka all shot .75" or better thier very first time out. No special heat cycles, no special bullets, shoot 3-5 rd groups and let it cool between. Just make sure to clean at the end of the day.

The purpose of barrel break-in is to extend the number of rounds that can be fired before accumulated copper degrades accuracy.

Many barrels do not need break-in. Some do.

If you take a new rifle to the range, shoot one round, clean with an ammonia based cleaner, and get significant blue on the patch, your barrel will probably benefit from break-in.

Even old barrels can benefit from break-in. I have a 1917 Swede that accumulated copper more than I liked. I carefully cleaned it down to bare steel, and did the shoot 1-clean routine for about 7-8 rounds. Then I did shoot 3-clean for about another 15 rounds. That's not a big project. Since then, I can shoot quite a bit more between copper cleanings.

If you use something like Wipe Out after every trip to the range, you probably won't notice the difference that break-in makes.

Avoid abrasive break-in procedures like the plague. They do nothing but wear your gun out. The throat retreats down the barrel like you'd shot your lifetime supply of ammunition through the barrel, and it's throat wear that usually sets the useful accurate life of a rifle.

Barrel life depends on many factors, quality of the steel used, types of powders, etc. I have read that some cartridges-the 220 Swift, e.g. are very hard on barrels, jacketed bullets wear a barrel faster than lead. Barrel Break In ? As noted, some people endorse it, others don't, so many different methods. A a very personal matter, no hard and fast answers.

I agree with denton, but would like to add a bit. My feelings are even with custom barrels that are hand lapped, the throat area where the rifling begins lacks some of the lapping that the rest of the barrel gets. What breaking in the barrel does IMO is to burnish any burrs helping to prevent copper build up.

I have started this process with the last few rifles I have purchased and noticed a difference particularly in the 3500FPS range and faster such as .204, 22-250, etc.as examples, in the ability to clean out the copper faster and not have such of a build up to start out with. As far as increased accuracy and barrel life, I doubt it has that much of effect.

I am a gun cleaning nut. I find that many of my rifles shoot better with a thoroughly cleaned barrel and start going south around 30 shots later. Although there are some that need 3-5 foul shots to be at there best which I believe is due to rough spots that need to get smoothed over a bit. Those rifles are in the minority. Patience and care must be used when cleaning to avoid damage and definately a bore guide.

As far as barrels being better than they were years ago, I guess that depends on how many years ago you may be talking about. I have some 20-25 year old rifles that have shot much more accurately out of the box than many do today.

If you want to see a very interesting short video reguarding barrels, go on the 6mmBR website and click on the barrel tab which is about 2/3s down on the left side. then click on the link factory vs. custom barrels. It's very enlightening.

I guess there are many diffent thoughts on the subject of cleaning. We all do what we think is right and that's the way it should be.

I see that Hodgdon has this new CFE223 powder that is actually supposed to remove copper fouling as you shoot. I'm a gadget guy and will have to try it sometime.

I do not break my barrels in. I feel guns rough enough to need break in it won't martter and high quality match barrels are already "broken in".

Hoo ha. I have found it to be a lot of nonsense. Shoot it, enjoy it, clean it. It's that simple.

This was posted by the famous Gale McMillan of McMillan barrels concerning this subject.

http://www.snipercountry.com/Articles/Barrel_BreakIn.asp

Gale McMillan
Senior Member posted September 25, 1999 10:10 AM
--------------------------------------------------------------------------------
The break in fad was started by a fellow I helped get started in the barrel business . He started putting a set of break in instructions in ever barrel he shipped. One came into the shop to be installed and I read it and the next time I saw him I asked him What was with this break in crap?. His answer was Mac, My share of the market is about 700 barrels a year. I cater to the target crowd and they shoot a barrel about 3000 rounds before they change it. If each one uses up 100 rounds of each barrel breaking it in you can figure out how many more barrels I will get to make each year. If you will stop and think that the barrel doesn't know whether you are cleaning it every shot or every 5 shots and if you are removing all foreign material that has been deposited in it since the last time you cleaned it what more can you do? When I ship a barrel I send a recommendation with it that you clean it ever chance you get with a brass brush pushed through it at least 12 times with a good solvent and followed by two and only 2 soft patches. This means if you are a bench rest shooter you clean ever 7 or 8 rounds . If you are a high power shooter you clean it when you come off the line after 20 rounds. If you follow the fad of cleaning every shot for X amount and every 2 shots for X amount and so on the only thing you are accomplishing is shortening the life of the barrel by the amount of rounds you shot during this process. I always say Monkey see Monkey do, now I will wait on the flames but before you write them, Please include what you think is happening inside your barrel during break in that is worth the expense and time you are spending during break in

Click to expand...