Barrel Break-in? Yes or no?

[greg788]

I've been searching the archive and cannot find consensus.

With a "good" factory rifle like Remington, Browning, etc. is barrel break-in necessary for optimal accuracy and barrel life? Or should I just clean and shoot? Or just shoot?

If barrel break in is optimal, should I go with something like Tubb's Final Finish?

 

[atlanticfire]

Shot it clean it . . . repeat. I only usually do it for like the first 20 rounds. Somehow I don’t think it really matters.

 

[ar10]

Yes.
Or no.

 

[USSR]

I've been searching the archive and cannot find consensus.

And you never will. Do what you think.

Don

 

[.38 Special]

No, you won't find consensus. You will find information. Choose the camp that has the ring of truth, in your opinion, and go with it.

For my money, great results have been had with and without break-in. That's a clue, as far as I am concerned.

 

[helz_mcfugly]

if its a new stainless barrel then yes, google "breaking in a stainless barrel". in other cases I would just shoot and clean, shoot and clean.

 

[John828]

really ought to sticky a thread like this

 

[rangerruck]

I do , but lightly. 1 shot, clean and lube, for each shot for 5 shots. then i take 5 shots, and clean and lube, after each 5 shots. do that for 25 shots, and i am all done.

 

[MCMXI]

if its a new stainless barrel then yes, google "breaking in a stainless barrel". in other cases I would just shoot and clean, shoot and clean.

I just finished breaking in two Krieger barrels (the throat actually), both stainless, following Krieger's recommended procedure:

5 one-shot cycles
1 three-shot cycle
1 five-shot cycle

They recommend removing ALL copper from the throat and bore during each cleaning. Their recommended procedure for a chrome-moly barrel is:

5 to 25 one-shot cycles
2 three-shot cycles
1 five-shot cycle

According to Krieger, tooling marks in the throat create a copper plasma which deposits copper in the barrel. Cleaning every shot for five shots polishes the throat and I noticed less and less blue coloration of the cleaning patches as I progressed. After the five-shot cycle, I cleaned the throat/barrel and didn't see any blue on the patch. I then shot 13 rounds in succession with zero copper fouling in the barrel at the end. In fact, the barrels are so pristine that I don't even use a brush. I simply clean them with an oiled patch.

My advice, follow the recommended procedure from the rifle/barrel manufacturer.

 

[Big Bill]

Here's what I do...

Sight it in...

Go home and clean it...

Let it sit for six months...

Go target practice with it...

Go home and clean it...

Let it sit until hunting season...

Take it hunting...

Clean it...

Next day, go back to the range and re-sight it in...

Clean it...

Let it sit for 3 months.

End of 1st year...

Beginning of new year, buy new gun! Repeate proceedure!!!

 

[W.E.G.]

Has anybody ever done an accuracy comparison test?

I'd like to know whether a "broken-in" barrel shoots better after some number of rounds than the "non-broken-in" barrel.

Its astounding to me that the barrel manufacturers don't have any such test-results for us to study.

Could it be that "the manufacturer's instructions" are just a perfunctory nod, existing only to avoid ruffling the feathers of those shooters who insist that "BARREL BREAK-IN IS ESSENTIAL!!!" ?

I put 200 rounds through my new stainless Krieger AR-15 barrel before cleaning it. After 5000 rounds it was still shooting 20-shot groups like this at 100 yards when fired with iron sights from a prone position with only a leather sling for added support.

Clearly, my barrel is ruined.

 

[USSR]

Has anybody ever done an accuracy comparison test?

I'd like to know whether a "broken-in" barrel shoots better after some number of rounds than the "non-broken-in" barrel.

Impossible to prove, one way or the other, since no two barrels are alike, even when having come from the same manufacturer.

Don

 

[MCMXI]

Has anybody ever done an accuracy comparison test?

I'd like to know whether a "broken-in" barrel shoots better after some number of rounds than the "non-broken-in" barrel.

I think that's going to depend on the discipline. If you're shooting with iron sights where 1/4 MOA groups AREN'T expected then perhaps barrel break-in is not necessary or even measurable. For benchrest shooters it may be essential and may be obvious.

Krieger doesn't say anything about accuracy and break-in but they do talk about fouling and that's what the break-in procedure is all about. I have a Remington 700 Alaskan Ti that still has copper fouling in the barrel after five-shot groups and maybe sooner than that. I've put around 100 bullets through the barrel and have to use Sweet's at the end of every session to remove copper. With that barrel I followed a break-in procedure using CLP, a copper brush and patches so I wasn't removing the fouling in the barrel. In comparison, both stainless Krieger barrels had zero copper fouling after only 8 shots following the Kreiger break-in procedure and using Sweet's 7.62 to remove the copper with each cleaning. After break-in, I shot 13 rounds through one and 10 through the other without cleaning and neither barrel had ANY copper fouling at the end of both strings. I literally clean the barrels with an oiled patch i.e. no brush which may improve barrel life since all I'm removing is carbon or other combustion related residue. As for the Remington, I'm going to start the break-in procedure again but this time I'll use Sweet's to remove copper during the process. Hopefully I'll end up with a barrel that doesn't have copper fouling after only five shots and ideally doesn't have copper fouling after any number of shots. It may be more accurate too.

So to me there's no question that a barrel is broken in when it no longer has copper fouling in the bore after 5, 10, 15 shot strings etc. The problem with a barrel that does foul after a few shots is that copper has an affinity for copper so the bore will be reduced (by some amount) with each shot. There's no question that this occurs but is the reduction in bore diameter enough to affect accuracy? For some ... no ... for others ... maybe. If you're trying to achieve the most accurate groups possible, you want the variables to be constants so if your barrel doesn't foul during a 10 shot string you've eliminated one variable.

What we need here is for a few benchrest shooters to chime in since they're at the top of the pile when it comes to accuracy. They'd most likely know if barrel break-in is necessary.

 

[Average Joe]

Shoot it, if that don't work, then shoot it some more.

 

[SaxonPig]

This would be #36.

.............................................

Barrel break in.

36. “Breaking in” a rifle barrel is probably just a waste of time. Some barrel makers recommend it while others do not which demonstrates a lack of universal agreement on whether it’s really necessary so it probably is not. Every formula for break in involves some combination of firing and cleaning. The fact that there are numerous different formulas should be evidence that nobody really has the definitive answer on the best procedure meaning there likely isn’t one. Simply shooting the rifle as intended will likely be all the break in required.

 

[MCMXI]

Some barrel makers recommend it while others do not which demonstrates a lack of universal agreement on whether it’s really necessary so it probably is not. Every formula for break in involves some combination of firing and cleaning. The fact that there are numerous different formulas should be evidence that nobody really has the definitive answer on the best procedure meaning there likely isn’t one.

This is basically true of everything in the shooting world. Let me give you one example of how confusing this can be. If you're considering a new barrel and you're wondering about having it fluted here's what four top barrel makers have to say:

Krieger

Q: How does fluting a barrel help?

A: Fluting reduces weight while increasing rigidity and lessening barrel vibration and whip. By exposing more exterior surface area, it also aids in cooling your barrel.

Shilen:

What about "fluting" a barrel?

Fluting is a service we neither offer nor recommend. If you have a Shilen barrel fluted, the warranty is void. Fluting a barrel can induce unrecoverable stresses that will encourage warping when heated and can also swell the bore dimensions, causing loose spots in the bore. A solid (un-fluted) barrel is more rigid than a fluted barrel of equal diameter. A fluted barrel is more rigid than a solid barrel of equal weight. All rifle barrels flex when fired. Accuracy requires that they simply flex the same and return the same each time they are fired, hence the requirement for a pillar bedded action and free floating barrel. The unrecoverable stresses that fluting can induce will cause the barrel to flex differently or not return from the flexing without cooling down a major amount. This is usually longer than a shooter has to wait for the next shot. The claim of the flutes helping to wick heat away faster is true, but the benefit of the flutes is not recognizable in this regard until the barrel is already too hot.

Lilja:

Q: Does fluting cause stress in a barrel?

A: We've been asked if machining flutes into a rifle barrel causes stress in the steel. The short answer is no, it does not. There are some operations in the manufacture of a rifle barrel that can cause stress to develop in the steel, but fluting is not one of them. To the contrary, fluting can and will relieve stress if it is already present. The same is true of any outside machining work performed on a barrel.

The type of stress that can exist in a barrel is called compressive stress. Under normal conditions the stress could form from two processes. When steel is manufactured, the round shape is formed through a rolling operation in the steel mill. This forming can be performed either hot or cold. Cold rolling generates a great deal of internal stress in the steel. Usually, with steel used for rifle barrels, this stress is relieved by heating the steel to just below its transformation or critical temperature. We have the steel mill that makes our steel do this as their very last operation, ensuring us that the steel is stress free when we receive it.

Secondly, stress can be formed in a rifle barrel during a cold forming operation, such as button rifling. Since no material is removed from the barrel when the rifling is formed, rather it is displaced, it causes compressive stress in the steel. If this stress is not removed, through a heat treating operation, it will remain in the steel where it can cause other problems. Any subsequent machining operations, such as turning the outside diameter of the barrel, will allow some of those stresses to come out. The result can be an opening of the inside diameter of the barrel, more so towards the muzzle where more material is machined away. It can and probably will also cause the barrel to warp. And if these aren't enough, the temporary heating and cooling of the barrel that occurs during normal firing will also let the stress come out by warping the barrel. Poor accuracy is the result.

Although a barrel would not normally be welded on, this can also cause stresses to form in steel. At times though, gunsmiths will heat barrels to sweat-on barrel bands and sites. Too much heat can cause some problems as well.

But, the fact remains that normal machining operations, such as outside turning, fluting, drilling and tapping site holes, etc. do not cause or introduce stress. They can and do allow residual stresses to come out of the steel though.

We flute about 50 rifle barrels per month and have never had a problem with our barrels related to fluting.


Hart

.... Should I flute my barrel?

Fluting allows you to use a larger diameter barrel with the same weight as a smaller barrel. The smallest barrel we will flute is .650 at the muzzle. We recommend that you allow us to flute your barrel, as fluting is done before the final lapping, thus allowing us to maintain our guaranteed specifications. We offer six flutes, eight flutes (minimum muzzle diameter of .870), interrupted fluting, and octagon.


So Krieger says yes, Shilen says no, Lilja says yes and Hart doesn't have an opinion. So where does that leave the consumer? Ultimately, we have to make our own decisions based on the information that's available to us. Since Krieger's break-in procedure is easy, why not do it? The worst thing that could happen is that it wastes some time so for my own piece of mind I followed their recommendations.

 

[DoubleTapDrew]

Has anybody ever done an accuracy comparison test?

I'd like to know whether a "broken-in" barrel shoots better after some number of rounds than the "non-broken-in" barrel.

Its astounding to me that the barrel manufacturers don't have any such test-results for us to study.

It would be impossible to tell if the results were because of the procedure or just variances in the barrels or guns. One gun/barrel might shoot .4 MOA right out of the box while the other identical model can't hold them to 1 MOA.

Just load up a bunch of mags and fire as fast as you can until the barrel turns bright orange. Extra points if it starts to droop, then quickly plunge it into a bucket of water. This is known as heat cycling and is excellent for break-in

 

[MP3Mogul]

I do think you need a new barrel, but I don't think it's something you did... looks like it was a bad barrel from the beginning.

 

[.38 Special]

Has anybody ever done an accuracy comparison test?

Sort of. Go to any benchrest match and ask who broke in their barrels and who didn't. Then compare their scores. You'll note no significant difference. Yet another clue...

 

[MCMXI]

Sort of. Go to any benchrest match and ask who broke in their barrels and who didn't. Then compare their scores. You'll note no significant difference. Yet another clue...

.38 Special, Do you know how often benchrest shooters typically clean their rifles during matches? Do they shoot a fouler or two, then a group of five, then clean?

 

[MAX100]

It is best to start with a premium barrel that has been hand lapped.

Breaking in a barrel may help some but most production barrels are just to rough to benefit much from it. Fire lapping a production barrel will probably improve it the most.

GC

 

[Frankl03]

This is a great post! It's very timely as I'm getting ready to break in a new rifle. This is my first bolt rifle and allot of this stuff is new to me. The rifle is a FN PBR XP.

I'm going to go with the method mentioned above:
One shot cycle 5 times
One 3 shot cycle
one 5shot cycle

I'm going to get a one piece cleaning rod and a bore guide to help with the cleaning process.

 

[NCsmitty]

This subject has been beat to death on many threads here.
My assessment is that the premium barrels are hand lapped to remove the burrs left in the rifling process. These barrels require far less break in than the cheaper, unlapped barrels such as the Adams & Bennett from Midway. The cheaper brands of rifles also can benefit from some break in, after all, the bullets are doing the lapping in of the burrs. By frequent cleaning initially, you will see the copper particles on the patch that would grab at the next bullet down the barrel if not removed, and so on.
I'm not denigrating the A & B barrels as I have one on my 6.5x55 Mauser. I spent many patches and brushings and I'm seeing good results now after about 40-50 rounds. The last 6 rounds out of it clustered in less than an inch at 100yds, and those were just break in loads.
I'm all for giving a new barrel a little TLC at break in.

NCsmitty

 

[MCMXI]

One benefit of following a break-in procedure of shoot/clean/shoot/clean etc is that it forces you to take some time between shots which in turn allows the barrel to cool. Most of the quality barrel manufactures agree that heat is a barrel killer so perhaps there is a method to the madness.

I'm going to go with the method mentioned above:
One shot cycle 5 times
One 3 shot cycle
one 5shot cycle

Frankl03, I'd suggest that you base your break-in on the condition of the patches. If you use a copper removing solvent such as Sweet's 7.62, as the barrel breaks-in you'll notice that it takes fewer and fewer patches to remove the copper fouling. On my Krieger barrels, after I completed the 5 one-shot cycles, I only needed one or two patches whereas at the start I needed five or six patches. After the three-shot group the patches came out clean (no blue color) so I was basically done. I still shot a five-shot group in each and cleaned after that but no copper fouling occured based on the color of the patches.

 

[John828]

Just load up a bunch of mags and fire as fast as you can until the barrel turns bright orange. Extra points if it starts to droop, then quickly plunge it into a bucket of water. This is known as heat cycling and is excellent for break-in

Oh man, oh man. Too funny. Sadly, somebody is going to google: "Barrel break-in" and this post will come up in the results. And somebody in this world is going to try it.