Gunsmithing Objective research on Barrel Break-in procedures

[Jeff in TX]

After many email requests I thought I'd repost the research I did on barrel break-in procedures. In addition I also added a short overview on Internal Ballistics 101 to help tie everything together.

This has been posted on many shooting boards over the years and has been modified as I uncover more information. This is a quick synopsis of my finding which has been generalized. I had lots of test results and data I looked through. It’s also not based on the opinions and hearsay. I set out to take an objective look of barrel break-in procedures. I wanted to find out if there was any hard fact evidence to support barrel break-in procedures or was it a waste of time. In the end all of the data I collected supported the fact that barrel break-in procedures are a waist of time and in some cases damages barrels. To research this project I spoke with a few metallurgists, originally three of our top barrel makers (Shilen, Hart and Rock) and have since talked with a handful of others including Bartlein and Broughton. I also talked with a few internal ballistic engineers and some our nation’s best gunsmiths.

A little back ground on myself. I have degrees in Engineering and Business Adminstration. I’m a data network engineer in real life. I’m an avid long range shooter and due to my knees gave up tactical competitions about 6 years ago. One of my hobbies is external ballistics and I enjoy reverse engineering new ballistic programs to see what ballistic models, mathematical calculations, formulas and algorithms the creator used. I have a pretty good knowledge on ballistics and long range shooting. By no means am I an expert, when I'm in doubt I talk with Bryan Litz. I have spent more time than I care to admit to trying to uncover the science behind the scene. With regards to this write up, I feel I've done a fairly good job with my research and conclusions. Though some may disagree with my finding which is fine.

Before blasting away at what I've written, offer insight supported by facts and test data and not hearsay or opinions. This is what I’ve tried to do. It’s ok to disagree as the more information we can get the better informed we are. Also remember my conclusions were the collective data from some of the best minds and subject matter experts in the business.

Back in the 2001/2 time frame I trashed a brand new Shilen stainless steel match barrel in under 400 rounds shooting moly coated bullets. Yes this was during the moly bullet craze and I jumped on the band wagon. Let’s just say I was not a happy camper. I live local to Shilen so after a few hand lapping jobs on the barrel which failed, Doug Shilen cut the throat section to see what was really wrong. The throat area showed the black moly ring of death which was so hard Doug could barely scrape it with the side of a flat head screwdriver. Let’s just say I’ll never shoot another moly coated bullet....ever!

After my new Shilen barrel was installed I set out to on a mission to understand this barrel break-in process and if I really needed it. After all this research my conclusion supported the fact that barrel break-in is a waist of time and effort.

Let’s talk barrel break-in shall we: I believe Kelly McMillan of McMillan rifles said it best, “This barrel break-in processes keeps us in business”. “This shoot and clean, shoot and clean every round or few rounds break-in process only damages your new match barrel and/or significantly decreases the barrel life”. Though I didn’t speak with Kelly on this subject I’ve read what he’s written and it mirrors my own findings.

Some barrel manufactures have now re-clarified their stance saying that a barrel break-in procedures helps to smooth the transition from the newly cut chamber into the throat area of the bore. Now there is some merit to statement except for the fact a cotton patch with bore solvent or bronze brush isn’t going to do squat to help remove any rough areas. Bullets passing down the barrel will help smooth the chamber/throat area. It may take just a couple of shots or it could take a lot, but it depends on how well the chamber/throat was cut and polished. Last I checked stainless steel and chrome moly steel is much harder than a cotton patch or bronze brush.

Speedy Gonzalez (Hall of fame bench rest shooter and one of the nation’s top gunsmiths) was a wealth of information as were the techs at Hart barrels. As Speedy says, “my $3000.00 video-bore scope doesn’t lie”. I've looked through lots of barrels at Speedy's shop while he was working here in North Texas. Looking through his bore scope I learned a lot and saw a lot of good the bad and the ugly when it comes to barrel and barrel maintenance. Speedy's video bore scope never lied. When looking through his video bore scope at the internal surfaces of trashed barrels, one thing we did see a lot of were cleaning rod marks. The cleaning rod marks showed too much cleaning with poor and improper cleaning techniques and equipment. This was also noted by the techs at Hart Barrels with regards to barrels they replaced.

There are probably less than a dozen individuals in the US that understand internal and external ballistic as well as Stan Rivenbark and Mike Rock. Stan is retired ballistic engineer from Raytheon Corporation and Mike Rock of Rock Creek Barrels. They both understood this whole internal ballistic equation more than all the others I talked with. This is because they worked on internal ballistics in their real lives, used state of the art test equipment to perform actual tests and record the actual data. They are true subject matter experts and both of their views points and explanations were very similar. A slight twist here and there and different approach but there test data and conclusion were the same. A lot of folks claim to understand all or part of the internal ballistic equation, but these people had the hard data to back up there statements and claims. I like solid test data and not opinions on what someone believes.

As I stated Stan and Mike Rock gave me some of the most detailed explanations on barrels and internal ballistics. Both were ballistic engineers and both have degrees in metallurgy (Stan has an masters in metallurgy); Mike was a ballistics engineer for the US Army for many years at the Aberdeen Proving grounds. When Mike worked at Aberdeen, the US Army used high speed bore videos with mirrors, thermal imaging and computers to analyze any and everything that happens when the firing pin strikes the primer and the round goes off. While working as a ballistic engineer for Raytheon Stan used similar equipment and processes to view and record internal ballistics though most of his work was focued around the .50 cal.

Before we begin take a step back and be objective. Ask yourself what you are trying to really accomplish by breaking in your barrel. What issues and/or problems inside the barrel need to be corrected or fixed? Now I do recommend cleaning your rifle after you purchase it to clean out all of the junk, oils and grease from the factory before shooting it, but also realize...

• The vast majority (99%) of shooters don’t own or have access to a quality bore scope to view the interior surface of their barrels.
• Without a bore scope to view the interior surface of your barrel what exactly are you trying to fix by a shoot and clean process?
• If there are burrs or machine marks from the machining process are they in the chamber, throat or barrel where are they located?
• Do the machine marks run parallel or perpendicular to the barrel finish?
• If there are high points and low points inside the barrel again where are they located?
• Does shooting and cleaning between rounds correct/fix all barrel imperfections if they exist? If yes how?
• Do you think cleaning between rounds is going to change the molecular structure of the steel or condition it in some fashion? If so, I’m/we’re all ears
• Without a bore scope again you have no idea what the actual condition of the interior barrel surface
• So far if you don’t have honest solid answers to these first few questions and you’ve been performing a barrel break-in process you’re working off a SWAG (scientific wild *** guess)
• Even if you have a bore scope can you truly identify a change in burrs or machine marks from a before or after cleaning. If so please provide detailed photograph’s

Couple more questions while I still have your attention.

• Pushing a cotton patch with solvent or a bronze brush down the barrel will do what to remove a 416 stainless steel or chromemoly metal burr or machine marks?
• Last time I checked, 416 SS or CM is much harder than a cotton patch or bronze brush and is most likely impenetrable by most bore solvents.
• Yes it will remove copper fouling caught by the metal burr, but how will it remove the metal burr?
• How many shots will it take to remove the burr or imperfection and how will you know when the barrel issues have been corrected? Is it always x-amount of shots?

Let's take a few minutes to gain a basic understanding of internal ballistics and what really happens when you pull the trigger. This will also help you to understand why you don't want to clean after every shot.

High level view of Internal Ballistics 101:

When the firing pin strikes the primer, the propellants in the primer ignites. With this initial ignition there may or may not be enough pressure to dislodge the bullet from the case (this depends on neck tension and seating depth as well as a few other variables), if there is enough pressure to dislodge the bullet, it moves forward into the lands where it stops. As the primer ignites the powder, more pressure builds moving the bullet forward where it can stop again. Once there is enough pressure from the round going off, the bullet is moved down and out the barrel. All of this happens in nanoseconds (billionths of a second). Your bullet starts and stops as many as two times before it leaves the barrel. This is fact. Bet you didn’t know that…….neither did I!

Internal Ballistics on the brass case:

As the primer ignites the powder, pressure begins to fill the brass case. As the pressure builds the case expands to completely fill the chamber sealing off the chamber and preventing any gases from leaking around it. The pressure will also cause the brass case to move rearward pushing it flush against the bolt face. In addition the shoulder and neck area of the case will be force forward into the shoulder and neck area of the chamber. All of this pressure will have elongated and lengthen the total size and diameter of the brass case. As the bullet is moved down and out the barrel, the chamber and barrel pressure drops. The brass begins to cool and contract allowing the brass to be extracted from the chamber.

Internal Ballistics on the bullet:

As the bullet is forced from the case, it can only support a small amount of force. The force on the base of the bullet will cause it to expand. As more force is applied the bullet expansion will increase from the base of the bullet towards the bullet nose. Basically the bullet begins to stretch. In addition the bullet enters the lands and grooves of the barrel. The bullet will engrave itself to the lands and grooves as it proceeds through the barrel. The throat of the barrel takes on the majority of stress from the heat and pressure created from the firing of the round. This is why the throat area of the barrel is always the first point of barrel deterioration. Depending on the round being fired the flash point of the round going off can cause instantaneous burst in temperature upwards to 4000 degrees Fahrenheit and create a pressure spike upwards toward 60,000 PSI’s.

Why thorough cleaning between rounds is not good for a barrel:

Think of a car engine for a moment. Why do we use oil in the engine? To prevent any metal-to-metal contact as well as reduce friction between two metal (bearing) surfaces. Your barrel is no different from the engine. If you clean every round or every few rounds during your barrel break-in process or clean your rifle so well after shooting that you take it down to the bare metal, you’ve created a metal-to-metal contact surface for the next time you shoot the gun. So what’s the problem with this you ask? Just like your car engine, metal-to-metal contact will cause friction which can sheer away layers of metal from each surface. So if your bullet is starting and stopping as many as two times before it leaves the barrel, that’s two places for metal-to-metal contact to happen as well as the rest of your bore. Even though copper is a gilding metal it can still sheer away barrel surface in the bore when traveling at high velocities under extreme heat and pressures.

Remember it is these copper jacketed bullets passing down the barrel at high pressure and velocity that will ultimantly be the source of smoothing out those rough marks left by the chambering tool and machining process. The more bullets passing down the barrel will help smooth the barrel not cleaning it between rounds.

Cleaning between rounds especially thorough cleanings can take you back down to bare metal which can actually harm your barrel. In addition all this cleaning, done improperly with cheap bore guides and cleaning rods can scratch and damage the interior surface of your barrel. This was very prevalent in the barrels we looked at through Speed’s video bore scope. To preserve your barrel you need to avoid cleaning down to bare metal. A light wash of copper fouling in the barrel is not always a bad thing, as the copper fills in a lot of the micro groves left by the machining process. You don’t want layers of copper which effect accuracy, but filling in the micro grooves can be a good thing.

So what do we need to really take care of our new rifle and/or barrel?

According to Mike Rock and the other barrel manufactures agreed, all you need to avoid this metal-to-metal contact is a good burnish in the barrel. Some barrel manufactures will void your barrel warranty if you shoot moly bullets. This is not to say that moly is necessarily bad for a barrel, but it can be when applied to bullets. Never shoot moly coated bullets as they are bad juju for the throat of a rifle.

There are numerous ways to achieve a good burnish in your barrel such as just shooting a long string of rounds without cleaning. I like Mike Rock’s method and have been using it on all my match grade and factory barrels.

When Mike re-barreled my tactical rifle with one of his 5R barrels, I talked with him about my new barrel, any barrel break-in process and how to get the best performance out of my new barrel. This is what he had to say. When he makes a new barrel, he hand laps the barrels with a lead lap. Most if not all custom barrel makers hand lap their barrels. Mike takes his barrels a step further to provide a pre-burnished finish. He uses two products from Sentry Solutions. One product is called Smooth Coat, which is an alcohol and moly based product. He applies wet patches of Smooth Coat until the bore is good and saturated and lets it sit until the alcohol evaporates. The barrel now has loose moly in it. Next he uses a second product for Sentry Solutions product called BP-2000, which is a very fine moly powder. Applied to a patch wrapped around a bore brush, he makes a hundred passes through the barrel very rapidly before having to rest. He repeats this process with fresh patches containing the moly powder a few more times. What he is doing is burnishing the barrel surface with moly and filling in any fine micro lines left by the hand lapping. He then uses a couple of clean patches to knock out any remaining moly left in the bore. He also included a bottle of each product when he shipped my rifle back which is what I’ve been using on all my other rifles.

With the barrel burnished with moly, this will prevent any metal-to-metal contact during the barrel break in process. My instructions for barrel break-in were quite simple. Shoot 20 rounds (non-moly bullets) with no cleaning, as this will further burnish the barrel. Done! Now shoot and clean using your regular regiment of cleaning and if you have to use JB’s or flitz type products, go very easy with them as they can clean the interior barrel surface back down to bare metal removing your burnish. Never clean so well you clean back down to bare metal surface.

He said most of the cleaning products do a great job, don’t be afraid to use a brush and go easy on the ammonia-based products for removing copper fouling. Basically don’t let the ammonia-based products remain in the barrel for long lengths of time.

What’s my cleaning regiment you might ask? I’m not one who puts his firearms up without cleaning them; it’s what I was taught growing up. I'm also not one who wants to spend a lot of time and effort cleaning so my process is pretty simple but highly effective. I use only a Lucas bore guide and Dewey cleaning rods, something I learned from Speedy. Most other bore guides will allow your cleaning rod to flex inside the barrel which can scratch the barrel surface...not a Lucas bore guide.

I clean my rifles using WipeOut Accelerator and WipeOut foam. I use a few patches soaked in WipeOut Accelerator just to push the bulk of the gunk out of the barrel and then give it a shot of Wipeout foam. Let sit for 3-hours or so and patch it out. If I know it will be a few weeks before I get to the range or lease I’ll run a single patch of kroil oil down the barrel followed by a couple of dry patches. The process is quick and simple and works well for me. I have one barrel on my sons Win Featherweight where we need use a nylon brush with a little JB’s to get most of the fouling out as it’s a stubborn factory barrel. I’m considering using Tubbs Final Finish on this barrel.

For badly fouling factory rifles, I know of quite a few folks who have used Tubbs Final Finish with very good to outstanding results. TFF are lapping compound impregnated bullets you shoot down your barrel which can really help smooth out and polish a factory barrel.

I’ve used my buddies bore scope quite a few times to see just how clean my process gets my rifles. My Bartlein and Rock barrels hardly ever foul so I rarely if ever see any copper fouling in those barrels. My DPMS and Tikka both show very light and faint traces of fouling here and there after cleaning. I figure that fouling is just filling in some of those micro grooves as well as I know I have a good burnish in the barrel and I don’t give it a second thought as they all shoot lights out!

I hope that helps folks to understand what I’m trying to say.

 

[427Cobra]

Re: Objective research on Barrel Break-in procedures

This should be a Sticky!

 

[DMann]

Re: Objective research on Barrel Break-in procedures

+1 on this being a sticky.

 

[Rafael]

Re: Objective research on Barrel Break-in procedures

Great post! One the best I have read in a long while.

Thank you, Jeff.

 

[spaniel]

Re: Objective research on Barrel Break-in procedur

I especially appreciate this with respect to the explanation on how premium barrels are prepared. This explains a lot about why my otherwise accurate factory Remington barrel fouls like no other. Guess I need to shoot more and burn it out.

 

[Victor N TN]

Re: Objective research on Barrel Break-in procedures

I've known Mike Rock for many years. This is pretty much what he told me back about 1992. Since then I have had the same discussion with 2 other barrel makers. They said pretty much the same thing.

I know a lot of people say this is something akin to "witchcraft". But I've done it on every new barrel (8 to 10) since Mike and I had this converstaion.

I agree. I think I'll make this a "sticky".

 

[cmh2007]

Re: Objective research on Barrel Break-in procedures

excellent read, thanks for the information.

 

[USMCj]

Re: Objective research on Barrel Break-in procedures

Nice read, but there is one part that needs a bit of editing I belive.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Some barrel manufactures have now tired to re-clarify their stance saying that a barrel break-in procedures helps to smooth the transition from the newly cut chamber into the throat area of the bore. <span style="font-weight: bold">Now there is some merit to statement except for the fact a cotton patch with bore solvent or bronze brush isn’t going to do squat to help remove any rough areas. Bullets passing down the barrel will help smooth the chamber/throat area.</span> It may take just a couple of shots or it could take a lot, but it depends on how well the throat was cut. Last I checked stainless steel and chrome moly steel is much harder than a cotton patch or bronze brush.</div></div>

I dont think anyone ever said it was the job of the brush or cotton patch to smooth out these areas, every bbl break in instruction I have ever read said it is the bullets job to do that. Now the reason to clean after each shot is because when the copper jacketed bullet hits these rough spot when it enters the throat, some copper atomizes and settles on these rough spots, and the next round fired does the same thing and the copper from that bullet attaches to the copper from the first round fired thus building up copper in the rough spots in the throat area.

The need to shoot one and clean until the throat is smooth (burnished) is to make sure you clean out the copper before you shoot the next round so it doesnt build up in the rough spots, I mean how is the bullet going to smooth out these machine marks left by the reamer if there is a crap load of copper sitting on said rough spots.....

This is how I understand it at least.

In my personal experiance, I have never had to shoot one, clean a custom hand lapped barrel more than 5 times to burnish the throat (lets just say Mike Rock makes some smooth ass barrels!)

 

[former naval person]

Re: Objective research on Barrel Break-in procedures

Has anyone researched the HxBN as far as leaving a "nasty ring" at the case mouth? Does it occur with that friction reducing agent or only with moly?

 

[USMCj]

Re: Objective research on Barrel Break-in procedures

I dont think HBN has any of the drawbacks that molly did. At least thats what everyone keeps saying.

 

[Rolex24]

Re: Objective research on Barrel Break-in procedur

Great post! I've been reading everything I could find on break-in as I wanted to start of on the right foot with my new Rem 7005R. Now I have what looks like the "right info". Thanks for taking the time to share.

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

I skimmed over this, didn't read in great detail BUT we need to be clear about a few things.

A top quality MATCH barrel is NOT the same as what many are running. totally different animal. Even then some "quality" ones show a decrease in build up by correct bedding.

Cleaning between shots is done so that you DO have "metal to metal" contact. It's done so that you ARE adding friction and increasing wear. You can't talk about it being bad than go on about using products designed to do exactly the same thing BUT increase wear more.

It is VERY easy to tell when a barrel is "done". You should see a dramatic drop in build up.


It's important not to present your post as being absolute fact. For MATCH quality barrels it's reasonably accurate. How many run this quality barrel?

 

[flyboy]

Re: Objective research on Barrel Break-in procedures

Who cares if your getting build up if the rifle shoots?

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

Everyone?
The less build up the longer you can accurately shoot, easier to clean when you have to, less chances of pressure increase, changes in POA, more stable over a longer time and mutiple other reasons.

If you can adjust your process for every barrel you tend to get the best results over a longer time. blanket statments of XX being all that is needed mean people have less chance to learn something useful

 

[acttacus]

Re: Objective research on Barrel Break-in procedures

I have a question for you barrel gurus, do buildup occur continuously with increasing number of shots? or does the buildup stop after it has reached a certain threshold?

I'm curious as, if the threshold theory hold, then one would never have to clean the barrel, as the pressure will remain constant after no more buildup can anneal to the barrel.

Just a random thought.

 

[Jeff in TX]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AUJohn</div><div class="ubbcode-body">

If you can adjust your process for every barrel you tend to get the best results over a longer time. blanket statments of XX being all that is needed mean people have less chance to learn something useful

</div></div>

AUJohn,

You make a good point but something I pointed out as almost impossibility. 99.9% of shooters don't have access to a quality bore scope to view the interior surface of their barrels and to see where or if any there are any imperfections. So how do you adjust your procedures for each barrel without knowing?

I'm fortunate, I have access to a Hawkeye borescope and my gunsmiths (Mike Rock, Mike Lau, George at GAP and Gene Williams, with Gene being the must meticulous IMHO) have all done phenomenal work fitting the barrel and cutting the chamber.

Even my factory barrels have responded well following Mike Rocks advice of shooting 20 rounds (non moly) bullets. Before shooting each factory gun I thoroughly cleaned it and prep the barrels with the two Sentry Solutions products provided by Mike Rock. After shooting 20 rounds and cleaning all checked out well under the bore scope except one. My son Win Featherweight .243 seems to foul a lot about 4” past the throat and for another 5”, though the throat looks great. I’m considering using Tubb’s final finish on his barrel to smooth out that section that continues to foul. His gun still shoots just under 1 moa which is great for featherweight.

As I’ve stated without a borescope you’re purely speculating and guessing at what you’re doing when it comes to shoot and clean which I don’t recommend.

 

[oneshot onekill]

Re: Objective research on Barrel Break-in procedures

Great Read!... While I agree that Breaking in a barrel does more harm than good and causes you to waste the best shots your rifle will ever make, I think there should be a little more emphasis placed on the damage done by Cleaning Rods during this process. I can't tell you how many times I've been at the range and watched someone go through their "Break-in" process and clean with a plain steel rod shoved in and out of the barrel like a Jack-hammer with absolutely no guide at all! An un-guided cleaning rod will ruin your barrel faster than ANYTHING! Why?... because of what many of them are made of and how much they contact the inside of your barrel. My cleaning rods are all either steel or fiberglass (Yes, fiberglass is harder than and extremely abrasive to your bore) but I go to great extremes to make sure they NEVER contact the inside of my barrel(Bore-guides and SLOW passes). By the way, my barrels only get cleaned when accuracy starts to suffer. Sometimes hundreds of rounds between cleanings

So... even if you do believe in a "Barrel Break-in" process... Please, Please at least "clean" your barrel... Don't wreck it!!!

John

 

[flyboy]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AUJohn</div><div class="ubbcode-body">Everyone?
<span style="font-weight: bold">The less build up the longer you can accurately shoot, easier to clean when you have to, less chances of pressure increase, changes in POA, more stable over a longer time and mutiple other reasons. </span>If you can adjust your process for every barrel you tend to get the best results over a longer time. blanket statments of XX being all that is needed mean people have less chance to learn something useful

</div></div>

But can you prove it.

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeff in TX</div><div class="ubbcode-body">
AUJohn,

You make a good point but something I pointed out as almost impossibility. 99.9% of shooters don't have access to a quality bore scope to view the interior surface of their barrels and to see where or if any there are any imperfections. So how do you adjust your procedures for each barrel without knowing?

<span style="color: #FF0000">Feel, looking at patches. It's not that hard</span>.

As I’ve stated without a borescope you’re purely speculating and guessing at what you’re doing when it comes to shoot and clean which I don’t recommend.
</div></div>

That's simply not true.

Maybe you can address the other points as well?

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: flyboy</div><div class="ubbcode-body">[
But can you prove it. </div></div>

Prove that guns which foul tend to drop accuracy? That carbon rings cause pressure and accuracy issues?
The copper build up changes pressure and vibration nodes, leading to accuracy issues?
You can't be asking me this can you? Unless you have little knowledge and experience you must know this so what are you asking? If I can take a factory gun and show this going on? Or a "bad" barrel? Sure, can't you? You could go so far as running a piezo system and WATCHING the pressure, vibration node and accuracy change. You knew this right?

 

[flyboy]

Re: Objective research on Barrel Break-in procedures

Broken in vs. Not broken in, Yeah, thats what I'm asking.

 

[Clark]

Re: Objective research on Barrel Break-in procedures

I am an electrical engineer.
When I design a test [for lightning, emi, battery charging, engine starting, that kind of stuff], I make sketches and wave my arms.
Technicians built the custom test equipment and build the test set up.
I sit in the same area and watch for any out of control variables.

In psycho-babbel, "It is easier to spot someone else's out of control variable than your own."

I don't believe in barrel break in.
To convince me, it would take a randomly selected population of each of several types of new barrels. The benefits of break in would have to be measured for each type of barrel.

Or so I thought.
This year a Lothar Walther 7mm barrel I chambered for 7mmRemMag was Copper fouling every few shots of moly bullets. I had to keep cleaning it, until that trouble stopped.

This year a Douglas factory blued and long chambered 260Rem barrel with a blued bore, that I head spaced and screwed onto an action.
It Copper fouled every few shots of moly bullets.


What does it all mean?
1) In the accuracy game, continuing a ritual is often easier than a controlled experiment to establish it is not worth doing.
2) I can keep on not believing in a ritual if I want... but I still have to clean out the Copper.

What does THAT mean?
If you believe in barrel break in or don't believe, either way, you can't say you know the answer:
http://en.wikipedia.org/wiki/Sampling_error

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

I think SOME need it, SOME don't. Match quality ones should NOT need it. Factory often do AND you can tell when.


We need a very clear line between MATCH and factory. Then we need to understand there is some overlap, some "bad" match, many "good" factory.


Anyone talking about fire lapping or similar IS talking about the SAME process.

 

[The_Punisher]

Re: Objective research on Barrel Break-in procedures

Interesting for sure.

 

[markspring1978]

Re: Objective research on Barrel Break-in procedures

Considering what GAP has posted on their website regarding barrel break-in (gaprecision.net) it would be interesting if George weighed in on this.

 

[flyboy]

Re: Objective research on Barrel Break-in procedures

He has in the past. I wouldn't expect him to repost it again.

 

[CK_32]

Re: Objective research on Barrel Break-in procedures

Thank you. I believed for so long breaking in barrels. Until i actually asked around and for some real facts about it my self.

I was kinda dissapointed MIDWAY USA has a video out.

when its a load of bull. My friend actually ruined his barrel trying to break in his new rifle.

 

[USMCj]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CK_32</div><div class="ubbcode-body">Thank you. I believed for so long breaking in barrels. Until i actually asked around and for some real facts about it my self.

I was kinda dissapointed MIDWAY USA has a video out.

when its a load of bull. My friend actually ruined his barrel trying to break in his new rifle. </div></div>

Just because your friend doesnt know how to break in a barrel, or properly clean one for that matter, doesnt make it bull.

If you read above, you will see that its not the barrel that needs to be broken in, its the throat and the marks left by the reamer.

 

[Greg Langelius *]

Re: Objective research on Barrel Break-in procedures

Just noticed this as I do some catching up after a couple of weeks between Internet access. Excellent presentation, backed by credible research. It would be self-serving of me to say that it confirms essentially all of my conclusions, but pretty much, that's just what it does.

Points; I realize the conclusions are based mainly on aftermarket/premium barrels, and apply differently regarding unhoned/unlapped factory barrels. With a factory barrel, I concur that firelapping can be of some benefit, that TFF is a good means of doing this, and I feel my own approach using JB for firelapping follows a similar concept.

The concept of burnishing corresponds to what I think of as 'seasoning' the barrel. I agree that fully stripping a bore is counterproductive, but abhor moly in all its forms, and might consider graphite as a naturally occurring fouling and burnishing agent that would probably serve well in moly's stead. 'Ring of death' aside, I just see the carbon/graphite as being easier to deal with, and kind of a no-brainer, as it's present as a propellant combustion after-product whether we choose to consider it as a positive aspect or not. It's my thinking that granule coatings consist mainly of graphite, that it does not burn, and that it's been doing the dry lube schtik that moly is intended to do for well over the entire past century. I've been beating this particular horse for years now.

Bare metal to bare metal makes me cringe. I consider gilding metal and carbon/graphite fouling to be something of a dry lube, negating the added complication of moly. I strongly believe in finishing any cleaning with a thin but thorough coating of oil, and that just prior to shooting, running a dry patch down the bore can help by wiping out any accumulated dust that may have attached itself to the oil film. Preferably, some of the oil film would remain prior to the passage of the first shot.

Fouling states and progress probably follow curves that differ greatly between barrels and loads. I figure there's three stages (at least); initial accumulation, a steady state where wiping and accumulation are roughly equivalent, and an end state where accumulation supercedes wiping. I see accuracy as being most consistent during the steady state, but also see bore conditions as being unique between shots, however small the variations, and that this uniqueness is one of the key factors affecting dispersion.

Once again, I read admonitions about long soaks using ammonia products, and once again, I wish someone would supply a rationale for the admonition. It makes sense alright, but knowing why, specifically, would help.

Finally, I'd be really interested if some of our resident internal ballistic mavens could help me understand if/how it could be possible to optimize a relationship between leade angles and ogive configurations.

Greg

 

[Clark]

Re: Objective research on Barrel Break-in procedures

Greg,
10 years ago, your power of suggestion had me putting JB bore paste on the bullets, to improve factory barrels.

I thought got away from all that with premium barrels, but now I have chambered some premium barrels that fouled fast the first two trips to the range.
Keeping them clean was, in effect, a break in procedure.
A procedure I don't believe in

 

[zenbiker]

Re: Objective research on Barrel Break-in procedures

I've felt for several years now that more barrels are ruined by cleaning than by shooting. I've watched guys at benchrest matches run 50 to 100 strokes through their barrels between relays. Even with a good bore guide, just <span style="font-style: italic">damn</span>.

 

[halfclue]

Re: Objective research on Barrel Break-in procedures

I am glad I took time to read this. There is so much confusing BS at ranges, gun stores, and some forums.

 

[Goatman007]

Re: Objective research on Barrel Break-in procedures

5 rounds, clean with one pass with solvent soaked brush from the BREACH, run 2 patches through bore. Repeat for the next 35 rounds, Barrel is broken in. Clean every 50 - 100 rounds there after. Using this method, I have even got Rugers to shoot well.(sub MOA)

 

[Clark]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Goatman007</div><div class="ubbcode-body"> .. I have even got Rugers to shoot well.(sub MOA).. </div></div>
Two years ago I got an old used Ruger #1V 223 from an on line auction for $500.
I cleaned out years of Copper.
I took it to the range, and shot (8) 5 shot groups.
All sub moa, one was 0.46".

What does it all mean?
Some Ruger barrels are good.

 

[stan462]

Re: Objective research on Barrel Break-in procedures

That for your time on this article. Great work explaining.

 

[g5]

Re: Objective research on Barrel Break-in procedures

Gale McMillan pretty much agreed, Jeff:

http://yarchive.net/gun/barrel/break_in.html

 

[TXHunter]

Re: Objective research on Barrel Break-in procedures

Guys, this is a great thread and i appreciate Jeff getting it started. I too live here in the DFW area and have spent some time with the smiths Jeff referenced. I had George at GA build me my first tactical rifle in 2002 after the accuracy of my factory 700 PSS went to hell due to excessive moly fouling. NO MORE MOLY EVER!! When I got the first rifle from George, I called and asked about break-in. He said that they had already done the break in during their test firing and I didn't need to. Just go shoot and clean after each shooting session or match. Prior to this, I had been introduced by Speedy to the Lucas bore guides and Dewey cleaning rods and all the other precision benchrest stuff. This first 308 from GA (Rock barrel) was outstanding. Sub .25 MOA until around 4 or 5 thousand rounds and a barrel burning stage at TacPro in 2006. The next rifle from GA (also a Rock barrel) was a 300WSM hunting gun for my son. Again I called George and inquired about break in. He told me to shoot and clean thoroughly after each shot and that the barrel would stop fouling around 12 to 13 shots. I used Butches for the first 5 wet patches, then 15 to 20 passes with a wet bronze brush, then 5 wet patches of Butches, then if there was still blue ( ie-copper still in the pores, cracks, etc), a few passes of Barnes CR10, wait a minute then dry patch. If still blue, then wrap a patch around a brush and soak with Rem Bore Cleaner which is like a liquid form of JB Bore Paste. Then test with CR10 to determine if copper remains. Most of this procedure was at one time or another recommended by Speedy and crew. Then dry patch thoroughly and run a patch of lock-eze down the tube prior to shooting. Lock-eze is a suspension of graphite in Alcohol. This was for a long time one of Speedy's strong recommendation so that there would be minimal metal (bullet) to metal (bore) friction/wear on the first shot down a clean bore. So, I did all this on my first range session and ran out of patches after 6 or 7 "break-in" shots. This barrel was fouling so bad I couldn't believe it. So I called George and left him a message. Then I called Mike Rock and left him a message. Aday or so later I got a message from Mike saying that he had also heard from George about my issue and that he ould be on the East Coast that week and would drop by and visit if I was anywhere near but that regardless, he guaranteed his barrels to shoot .25 moa and he would replace it if it didn't. Well, the week passed and I headed back out to the gun club with plenty of patches and other supplies and spent the majority of that saturday doing the same thing until I hit 13 rounds of this insane fouling/cleaning regimen. Then as if by pure magic the damn thing stopped fouling. I mean really stopped. You could shoot a group, run 5 wet and 5 dry, no brushing, test with CR10 and no blue. And this barrel has been like this ever since. My point is that this shoot and clean thing seemed to properly burnish this barrel. Since then, I have had numerous new custom barrels and a few factory ones. I have never seen another custom barrel take this long to stop fouling. Most stop around 2 or 3 shots. I don't spend this much effort on any factory barrel since I don' think they are worth the energy and time. I shoot a few rounds and clean thoroughly once and then get on down the road to shooting them. If they aren't reasonably accurate, I sell them or re-barrel them. I've been strongly advised by Bartlein, Stick at S&S, Gene Williams and others to never use the Tubb final finish on a custom barrel. But on the other hand, Todd Reynolds who I respect swears by the Tubb stuff.

In summary, i'm not attempting to disagree at all with Jeff or others. I'm just posting some empirical experience along the same lines and with some of the same people. I too continue on the quest of determining the optimum approach to this subject and would gladly modify my approach. In fact, I have several new barrels to break in and I'm going to shoot groups from the very start and clean after 10 shots to see if there is any discernible pattern to the fouling and accuracy. If interested, I will post further thoughts.

Best Regards to all.

 

[Supersubes]

Re: Objective research on Barrel Break-in procedures

Thanks for the post Jeff,

I agree completely however the gun scrubbers will continue to waste their time fiddling with their bores. It is like a sickness. A long as they guage fouling by the amount of time it takes to get a white patch to come out the other end of the bore, they can never see the truth.

I think every gun scrubber reaches their own personal threshold for string length and they start to get that itch. Then they magically get fliers and they think "it's time to clean".

I could go on and on but all I know is it has been months since I passed a patch down the bores of my two most used rifles, they were not broken in, and I shoot alot. I'd say each has over a thousand rounds down the tubes from the last cleaning. This is totally consistent with all of my rifles, and a lot of other rifles here.


Evil secret: It has been rainy here lately and the humidity caused the copper fouling in my .223 bore to turn green, clearly visible in the muzzle. That almost got the gun scrubber to come out of me but instead I just shot the shit out of it anyway. It's still rings steel way past transonic range.

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">

Bare metal to bare metal makes me cringe. I consider gilding metal and carbon/graphite fouling to be something of a dry lube, negating the added complication of moly. I strongly believe in finishing any cleaning with a thin but thorough coating of oil, and that just prior to shooting, running a dry patch down the bore can help by wiping out any accumulated dust that may have attached itself to the oil film. Preferably, some of the oil film would remain prior to the passage of the first shot.

<span style="color: #FF0000">If you have an issue with stripping a bore back then you should have an issue with fire lapping or abrasive products. It's using the same method to get the same result. An abrasive.
Do you think the factory lubricant and coolants are in the micro fissures? I would. I doubt we can ever get a bore totally "clean". While not directly comparable we should think about Engines running in. It's much the same process BUT can be done in mutiple ways. Lapping of some sort, firing and cleaning. In the end the quality barrel should need very little of it. The factory one is likely to need something for optimal accuracy over long periods of time.</span>


Once again, I read admonitions about long soaks using ammonia products, and once again, I wish someone would supply a rationale for the admonition. It makes sense alright, but knowing why, specifically, would help.

<span style="color: #FF0000">I have seen an accurate explanation of this issue. I can't recall where. From MEMORY the issue is not the ammonia but what's going on when it evaporates in the bore. Imagine a bore left standing full of it. The space left exposed after evaporation would pit. A bore full of it should not be an issue, one which is given to much time and the right conditions IS. I use it, I will continue to use it BUT my processes don't allow for the damage to happen. </span>

Greg </div></div>

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Supersubes</div><div class="ubbcode-body">Thanks for the post Jeff,

I agree completely however the gun scrubbers will continue to waste their time fiddling with their bores. It is like a sickness. A long as they guage fouling by the amount of time it takes to get a white patch to come out the other end of the bore, they can never see the truth.

I think every gun scrubber reaches their own personal threshold for string length and they start to get that itch. Then they magically get fliers and they think "it's time to clean".

</div></div>

This sort of post is what concerns me. It shows a real lack of understanding of what is being discussed.
There IS a "break in period" with barrels. If you buy a custom/decent one it should already be done.
What do you think "lapping" is? Why do you think they push for a certain end finish of the product?
Factory is quite different. Attacking people who are trying to throw some light on this, who understand the subject AND want an informed community is not on. I don't think it's possible to be knowledgeable on this subject and not know that some barrels NEVER settle down, others DO need to be cleaned often or the accuracy drops off. I toss any that I end up with.

I do what each barrel needs. If it needs nothing it gets nothing. If it needs to run in it gets it. the second it's settles down I don't worry about it. I then only clean if it needs it OR just enough to stop rust or other problems if it's not being shot for some time. This is how we should all be. Only by understanding what is going on can we not be ignorant and use a process which gets the best results. If you don't care, great. Just don't attack those that do

I would love to have some feedback on the points raised with the OP's post. At the very least it would be nice to see him understand the difference between factory and custom. The acceptance of partially correct information can be just as misleading as totally incorrect information.

 

[Supersubes]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AUJohn</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Supersubes</div><div class="ubbcode-body">Thanks for the post Jeff,

I agree completely however the gun scrubbers will continue to waste their time fiddling with their bores. It is like a sickness. A long as they guage fouling by the amount of time it takes to get a white patch to come out the other end of the bore, they can never see the truth.

I think every gun scrubber reaches their own personal threshold for string length and they start to get that itch. Then they magically get fliers and they think "it's time to clean".

</div></div>

This sort of post is what concerns me. It shows a real lack of understanding of what is being discussed.
There IS a "break in period" with barrels. If you buy a custom/decent one it should already be done.
What do you think "lapping" is? Why do you think they push for a certain end finish of the product?
Factory is quite different. Attacking people who are trying to throw some light on this, who understand the subject AND want an informed community is not on. I don't think it's possible to be knowledgeable on this subject and not know that some barrels NEVER settle down, others DO need to be cleaned often or the accuracy drops off. I toss any that I end up with.

I do what each barrel needs. If it needs nothing it gets nothing. If it needs to run in it gets it. the second it's settles down I don't worry about it. I then only clean if it needs it OR just enough to stop rust or other problems if it's not being shot for some time. This is how we should all be. Only by understanding what is going on can we not be ignorant and use a process which gets the best results. If you don't care, great. Just don't attack those that do

I would love to have some feedback on the points raised with the OP's post. At the very least it would be nice to see him understand the difference between factory and custom. The acceptance of partially correct information can be just as misleading as totally incorrect information. </div></div>

Sorry John, I just don't agree. Your saying the same thing over and over. I contend, from my own experience, that i can shoot and clean or just shoot the thing, and end up at the same place. l'll pick the one that doesn't waste my time. I've done that more than a few times now and it always turns out the same. Why is it that your experience is so different, one barrel wants this while the other wants that? Break-in procedures have been passed along from shooter to shooter based on theory and anecdotal evidence alone. Like the OP, I too have easy access to a borescope and decades of gunsmith knowledge(friends), and this is how I arrived where I'm at. MY shooting has improved and I'm getting very consistent results on target.

 

[AUJohn]

Re: Objective research on Barrel Break-in procedures

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Supersubes</div><div class="ubbcode-body">
Sorry John, I just don't agree. Your saying the same thing over and over.

<span style="color: #FF0000">for sure, since most of you seem to be missing a BIG factor here. Factory VS match.</span>

I contend, from my own experience, that i can shoot and clean or just shoot the thing, and end up at the same place. l'll pick the one that doesn't waste my time. I've done that more than a few times now and it always turns out the same.

<span style="color: #FF0000">With what? Factory? which? How many? It's all very well to claim you think it's a waste of time but the fact is all quality barrels ARE "broken in". Why?

</span>

Why is it that your experience is so different, one barrel wants this while the other wants that?

<span style="color: #FF0000">I don't know what you have done, what you shoot, how much, if you can tell one gun from another. I DO know that EVERY quality barrel has it done in some form and factory rifles don't. Some DO need it more than others. It's a process to use when it's needed. A statment of it being a waste of time yet every custom barrel has it done is at best odd. </span>

Break-in procedures have been passed along from shooter to shooter based on theory and anecdotal evidence alone.

<span style="color: #FF0000">Yet every single "quality" barrel maker does it in some form

Factory guns are not (well, a few are). So WE end up with a gun that is likely to need some shooting before it preforms at it's highest level. This can include "running in" in many cases. </span>

Like the OP, I too have easy access to a borescope and decades of gunsmith knowledge(friends), and this is how I arrived where I'm at. MY shooting has improved and I'm getting very consistent results on target.

<span style="color: #FF0000">So none of the custom barrels, none of your gunsmith friends laps in ANY form on any barrel

IF you understand what is being said you will see why I am concerned about misleading information being posted. A statment of it being a waste of time was made yet there is no doubt the process is done by barrel makers. THEY have ALREADY done it. On a factory or low end barrel it's not been done. Is the factory barrel so good it will not need it yet the quality ones does? </span>
</div></div>

 

[Supersubes]

Re: Objective research on Barrel Break-in procedures

I already said this but i'll quote myself here

"I contend, from my own experience, that i can shoot and clean or just shoot the thing, and end up at the same place. l'll pick the one that doesn't waste my time."

Comparing what you do to the custom barrel maker using a lead lap to put his final finish on is a stretch. Either way refer to what i said above.

Agreed, some barrels are shit and should be thrown in the trash.

 

[sharac]

Re: Objective research on Barrel Break-in procedures

All i can speak of is my Tikka, cleaned it once before shoot to get factory grease out and shot it in series of 50-70 shots in two sessions, cleaned after first session. Both times results were great and way above my expectations (best 5 shot group being .19MOA). As for copper fouling 1 patch of patchout and 5 minutes of dwell time and its clean. What is the bore like don't know and atm don't care since it's shooting great. If i had problems with it i'd sure use a borescope to inspect it before setting out on cleaning/lapping/voodoo crusade.

As said before cleaning and inspecting patches goes only so far without bore scope one is playing lottery. Voodoo magic just doesn't work for things it might work for you to convince you your bore is in excellent shape however until you make a looksee through a bore scope that will be a belief and not a fact.

 

[RemingtonSPS]

Re: Objective research on Barrel Break-in procedures

I am new to building rifles. I have had the priveledge of being tutored by my local barrel company. We have come to be good friends. I recently chambered a 7x300wsm. After chambering I looked at the throat thru a bore scope. You can clearly see the half moon shape of where the throat was cut. It doesn't appear rough. Ron (the owner of Benchmark) told me that that area is the area people attempt to smooth out in the break in process. He then taught me a simple effective trick. Using a patch and jag he applied some chromolly polish and gently patch lapped the throat. When we cleaned away the polish and looked at the throat again you could hardly see the half moon shape of the throat. It was very smooth and shiny. I did a break in process anyway on that barrel even though it wasn't needed and there was hardly any blue on the patch. That rifle shot awesome. Needless to say i will be patch lapping the throat on all my future builds and will not be doing a break in process. As a side note...I use a nylon brush about every 200 rounds and Breakfree only to get out the carbon. The barrels i have foul so little that i have found it unnecessary to clean out the copper. All my rifles are solid and consistently competitive.

 

[737shark]

Re: Objective research on Barrel Break-in procedures

Does anybody have the Norma USA representative name and contact info? PM or prefer email [email protected]

David

 

[thefiremeister]

Re: Objective research on Barrel Break-in procedures

I don't have the professional contacts that that Jeff has and I have never really been able to talk to any experts about barrel break in so its nice to see some else call bullshit on copper bullets smoothing out the bore of a rifle.

shoot one round and clean so the next Copper round you shoot will eliminate machining and tool marks has never made made sense to me

My last break in consisted of shooting for groups at the range and cleaning the gun at home.

 

[filefish]

Re: Objective research on Barrel Break-in procedures

interesting read, I have 2 "varminter" rifles, I broke them both in properly, whatever that means.. in my case it was wet patch/ dry patch every round for the first 20, then every five for the next 80. I was not all that convinced it would do much but "everybody" told me I must (funny but break in procedures are a lot like religion, everyone has their own, and if you don't do it their way, you are going to hell) anyways, I kinda hybrid my break in from what "everybody" told me to do... I can say this, my .223 is an off the shelf DPMS 24"bbl upper and it shoots .5" at 100 with my hand loads and the .308 is another DPMS 24" bbl I got on gun-broker for $40, granted, it was re-chambered and timed by an anal retentive perfectionist to work on my Armalite upper, but it shoots 3/4" at 200 yards. So, did I get lucky or did the break in work, I have no idea, but I will continue to use my break in procedure in the future

my $0.02

 

[jeffm]

Re: Objective research on Barrel Break-in procedures

This is interesting, but I am skeptical about the bullet stopping up to three times before leaving the barrel. I would think the bullet would tend to accelerate the entire trip down the barrel. I know that there is a point where a barrel is longer than the burn of the power, but for the most part I don’t see the bullet stopping. I have seen squibs (rounds with only a primer) push a round an inch or so into a barrel. I can’t help but believe that by the time a round is an inch into the chamber the power would be fully ignited. Tell me why I’m wrong.

 

[bucketofguts]

Re: Objective research on Barrel Break-in procedures

Excellent read! Thanks for taking the time! ~~~~~~~~~~~~bog