science or myth behind barrel break in ???

[PVL]

without trying to get in a peeing match... to someone with a bore scope... it would be nice to see some pictures before, a couple at various stages during, with a round count & after break in, to show that copper bullets can smooth out rifling imperfections...

otherwise I have a hard time believing a hand full of copper bullets & a few passes with a brush would remove the "waves" visible in the bore pictures posted previously

I would have a hard time believing a hand full of copper bullets & a few passes with a brush would remove the "waves" visible in the bore pictures posted previously, too.

That's why I never said or implied anything of the kind.

Without trying to get in a peeing match... - How about responding to what is actually said, instead of arguing with yourself over something that you made up?

Since nothing other than copper-clad bullets going through the bore were there to smooth out the roughness to some extent, I think we can use simple logic and safely assume that those copper-clad bullets were the culprits.

One time I needed a hole in a chunk of 1/4" angle-iron on a boat trailer... We didn't have a drill on hand, but we did have a Browning Stainless Stalker in .300 Winchester magnum. - A bullet from the Browning, made of lead covered with copper did a fine job of drilling a clean hole right through that steel.

When we talk about what goes on within a rifle barrel, it serves us well to keep heat, pressure and velocity in mind. A chunk of copper thrown by hand at steel will have little if any effect... A chunk of copper traveling at high speed though, followed by high pressure, very hot gasses is another story.

If you dig around for it ( I won't do it for you ) you can find videos of very high pressure water jets cutting right through steel in an industrial process that came out a decade or two ago. Hot, high velocity gasses are what eats out the throat on magnum rifle barrels... If gas can do that, imagine what copper-clad lead can do, despite being at a much lower temperature.

9-11 truthers insist that steel cannot be melted or weakened by fire... This kind of misconception is, regrettably, much more common than it should be. In the case of the 'truthers', the public school system failed them by teaching them what to think, instead of teaching them how to think.

[Magnum Wheel Man]

PVL... sorry if you thought my comments were a personal attack, as it was not intended, & in fact, you are not the only poster on this thread that said they had a bore scope you are however the only one that posted pictures, which I do appreciate... your last response seemed to me, to be a personal attack... I'd like to keep these discussions civil, & thus keep the thread open for discussion...

... yes I'm well aware of bullets shooting holes in steel, & also understand the theory behind water jet cutters...

... however there is a huge difference between a bullet smashing a piece of steel at 3000 fps at any set distance, & a bullet sliding along a groove that it's nearly been in contact with to begin with... I'm sure the water jet cutter works at best efficiency, when spraying directly onto a piece of steel, & probably won't cut efficiently at all, if just sprayed across the surface paralel with the steel...

... & in fact, it could be possible that the gasses do as much to remove the burrs discussed during chamber reaming, as the bullets do them selves, as throat erosion is generally thought of being caused by the gasses... & since the discussion is "break in"

the basis of my question is...how are those few handfulls of bullets with a few strokes of the brush in between, any different from several typical range sessions with cleaning in between???

[Brian Pfleuger]

The trouble with all this theory is that it's all virtually unprovable. You'd need a whole bunch of barrels as close to identical as possible. Just buying "identical" guns wouldn't be enough. You'd have to make sure the barrels, chambers, leade, rifling, internal surfaces and dimensions, were as close to identical as possible. I think you'd need at least 20, broken into 4 groups of 5. Then you'd need identical ammo, that's easy. Then you'd have to do the experiment, which would require hundreds of rounds through each gun, since you'd have to shoot statistically significant groups and at various ranges. You're talking probably 10,000 rounds.

Otherwise, we're left with speculation and comparisons between non-like situations, a lot like saying it's cold in Fl because I'm in NY and it's cold here, or I had a Honda that was junk so all Hondas are junk or my Saturn was awesome so all Saturns are awesome. (I'm sure somebody had a reliable Saturn, somewhere. )

[JD0x0]

Maybe we should email the Mythbusters about this. They seem to enjoy testing firearm myths.

[SaxonPig]

I'm no expert, but here's what I see.

Some barrel experts insist break in is absolutely necessary.

Some barrel experts say it is not.

There are numerous break in procedures. Many ideas on how to do it rather than one universally accepted formula.

All of this tells me there is no definitive answer to the question on whether it is required. If there is no definitive answer, it's probably no.

My answer is simple. If YOU think it helps, then do it.

PS: I have agree that it would take thousands of rounds for a copper covered bullet to wear the tempered steel of the barrel. Shooting, 10, or 100, would have an effective influence of zero. So shooting a small number of rounds to smooth or polish the steel of the barrel strikes me as myth.

[Bart B.]

JD0x0, asking Mythbusters to check it out's a good idea.

Maybe we should also have them check out an other "myth" claiming chambered rimless bottleneck rounds rest in the bottom of the chamber when they shoot their bullet into the bore.

[Jimro]

Maybe we should also have them check out an other "myth" claiming chambered rimless bottleneck rounds rest in the bottom of the chamber when they shoot their bullet into the bore.

Or rehash the differences between 7.62x51 and 308 Win or the differences between 223 Rem and 5.56x45? Or does a spitzer bullet turn upwind or downwind in a crosswind?

How many angels are we talking about on the pinhead again?

Some things are never going to get resolved, in my opinion.

Jimro

[Bart B.]

Jimro, everything gets resolved. Some don't like the results. Just like folks belonging to the Flat Earth Society and sticking to their beliefs. Their sister organization's the "We Never Went To The Moon" folks.

[PVL]

The break-in procedure that I use on button rifled barrels takes about 100 rounds or so, and I have noted a steady improvement in accuracy as the break-in progresses that generally levels out after 100-200 rounds.

I have never kept a rifle long enough for accuracy to degrade, but I have owned a few that were already that way when I got them. Here's the transition from the throat area to the rifling from a Mark X Mauser in 7mm RM that looked really low-mileage on the outside, and a peek down the barrel with a bore light showed what looked like a shiny new barrel:



Click image to see it larger

I finally concluded that somebody must have played "The Rifleman" with this gun, shooting it quickly without letting it cool down between shots. - It's the only explanation I can think of for a new-looking rifle to have its throat cooked so bad.

I saw something very similar on a nice little .243 that I bought used, one time. The rifle looked pristine, a peek down the bore looked good - but when I got it home and bore-scoped it, I knew I'd been had. So far, I've never gotten good accuracy out of a gun that had the throat area fried like that.

Strangely enough, I have not seen nearly as much improvement in accuracy as the first 100-200 rounds are fired from barrels that look pretty smooth to start with, hammer forged barrels for example. They do however become less 'sticky' after a while, and copper does not adhere so readily. - Sometimes I think it may be due to a thin, persistent carbon build-up instead of polishing that causes this to happen. ( At least in part ) Like the carbon-based non-stick finish one gets on a seasoned cast-iron skillet.

[reynolds357]

We went to the moon? I must have missed that. Would the bottle neck cartridge lay on the bottom of the chamber when being fired on the moon?

[Jimro]

We went to the moon? I must have missed that. Would the bottle neck cartridge lay on the bottom of the chamber when being fired on the moon?

Only if the astronauts wore heavy boots...

Jimro

[4runnerman]

We went to the moon with a gun and broke the barrel in?... Now that is a myth buster show I want to see. They could do it i Area 51,like we did.
Back to reality here, I agree with most- If it makes you feel good to break in a barrel-do it. I am in that group.

[Bart B.]

2 like barrels from same MFG will never be the same.

I've shot the same load in several makes and bore dimensions of 30 caliber barrels with 30 caliber magnum cartridges. They all shot with the same accuracy, even those of the same make.

Exactly how much difference is there between barrels of the same make if they're all top quality ones?

I've shot barrels with visible chatter marks from reamers, buttons, broaches and single-point cutters on the lands and grooves all with exceptional accuracy. I don't care what the inner surfaces look like, just how they shoot.

[Double Naught Spy]

Some things are never going to get resolved, in my opinion.

Jimro, everything gets resolved.

No, a lot really doesn't get resolved and this will never get resolved if somebody doesn't sit down with a few dozen barrels, devise a proper evaluation scheme that compares various break-in methods vs. non-break-in normal shooting to determine if there is truly any difference or not and nobody seems apt to do that. At best, somebody might try a singular break-in method on a single rifle against the same model that is shot normally. Whatever the results are, people will claim the test to be invalid due to sample size, and be right.

For all those who are saying this expert says this and that expert says that, just because they are experts in some field doesn't mean they are experts in this particularly unique process. Appeals to Authority is a logic flaw that gets a lot of people in trouble when making arguments and that is exactly what is going with several posts here. Unless the expert has done the necessary testing or has insight into testing none of us knows about, then what the 'expert' is saying is only as valid as the rest of our opinions.

[Brian Pfleuger]

Originally Posted by Bart B.

Exactly how much difference is there between barrels of the same make if they're all top quality ones?

If they're all top quality ones, probably not much, but they aren't all top quality ones. We're not talking competition winning custom guns here. (Which I imagine are almost all hand lapped anyway)

I suspect there's a reason that so many folks buy carefully crafted custom barrels and probably a reason (besides marketing lingo) that makers advertise things like "air gauged" and "hand lapped".

I doubt folks are buying custom barrels even though all the major gun companies barrels are all the same and all good.

When somebody asks what the best barrel is for a Rem700 or Savage, no body says "Just keep the stock one! It's as good as you'll get!"

[Jimro]

Brian,

I like folks who take off factory barrels. Keeps the price for takeoff barrels down.

Jimro

[reynolds357]

I just bought 3 take offs a couple months ago.
$60 each for Remington stainless .270Win. .270 WSM. and 7Rum. I am building the WSM now and the other two are spares.

[Metal god]

I see a lot of people trying to use logic in this hole debate . So here's a little of my own .

If barrels NEVER need a break-in . Why do people lap them ? Is that not a way to break in a barrel ? Thats just very soft lead , how can that do anything compared to a harder metal like copper or a bi-metal .

My point is barrel makers do break there barrels in . It's just done in different ways . I agree that a custom $1k dollar match barrel is as good as it's ever going to be when you take it out of the box . What about a Mossberg MVP or DPMS barrel ? I think the lesser QC quicker made barrels could very well need some help to get them to shoot a little better .

Then there's all the different ways rifling is put into the bore . I here hammer forged barrels would not need any type break-in .Lapping or other wise because the bore was never cut . Therefore leaving no burs or tolling marks that need to be smoothed out .

To give a blanket statement that no barrel can benifit from a barrel break-in just can't be true IMO

I think the better question would be . How many of us are good enough shooters to notice if it helped ?

[Jimro]

If barrels NEVER need a break-in . Why do people lap them ? Is that not a way to break in a barrel ? Thats just very soft lead , how can that do anything compared to a harder metal like copper or a bi-metal .

Just a few notes on lapping. Barrels are lapped as part of the manufacturing process to smooth out imperfections in machining and create more uniform dimensions. The lap is made of lead, but the lapping compound is not, it is an abbrassive, the lead is simply there to carry the abbrassive, so it can do quite a lot compared to naked copper or bi-metal.

If you put abbrasives on any metal, it will etch and wear away steel.

Jimro

[Jim243]

In the case of the 'truthers', the public school system failed them by teaching them what to think, instead of teaching them how to think.

Some things are never going to get resolved, in my opinion.

But, like I said earlier, folks oughta do what they think is right and not worry about what other folks do or don't do.

I think the better question would be . How many of us are good enough shooters to notice if it helped ?

I had a Honda that was junk so all Hondas are junk

Actually all cars are junkers, but we won't get into that.

Something has to be wrong here, people are giving advice that I can actually agree with (LOL)

Jim

Just sitting on the sidelines on this.

[Bart B.]

Note that good barrels inner diameters are measured to 4 or 5 decimal places from one end to the other. Tight spots are lapped more until tolerances are met.

How many folks breaking in barrels with bullets know how uniform that hole is when they think they're done?

[Double Naught Spy]

To give a blanket statement that no barrel can benifit from a barrel break-in just can't be true IMO

Likewise, to give a blanket statement that every barrel will benefit from a break-in just can't be true either, can it?

I think the better question would be . How many of us are good enough shooters to notice if it helped ?

Better questions...How many would know how to properly assess the condition of their new barrel and determine the correct course of action for breaking in the barrel. Obviously, if not all barrels are the same, then not all barrels are going to require the same break-in, are they?

Not only should you question how many here are good enough shooters to notice if it helped, but how many shooters here are good enough to actually understand exactly why and how it could have helped versus just normal shooting.

Barrel break-in for a lot of people is something akin to a religious experience, taken entirely on faith, with no ability to verify, and practiced as a ritual for each gun. It is a proverbial baptismal by fire as a blessing for better accuracy. Rituals performed vary by individual beliefs.

[Metal god]

good point Jimro thanks

How many folks breaking in barrels with bullets know how uniform that hole is when they think they're done?

^Not the point ^

Point is - can any type of barrel break-in help . Who's doing it , how there doing it and if there any good at it is not the question IMO . If that were the question you could ask if cleaning the rifle at all helps . Some do it much better then others . The guy that runs a dry bore snake down the bore is not doing much to clean the rifle . The guy that uses all the things we all know help remove the fouling to get the firearm clean will do a much better job . Then theres the using the right tools part . If you chuck your cleaning rod in to your drill and clean from the crown to the breach . Your going to destroy your bore and it would be best not to do anything at all rather then clean the firearm .

Now if you want to talk about how when and to what type of barrel you do a break-in . That could be a constuctive and interesting debate

I believe my point is still valid . To say barrel break-in will not help any barrel in any way is incorrect .

[Art Eatman]

And as is usual by Page 4, we're starting to around in circles.

Whee! Big wheels!