barrel break in

J

jcf0721

Private
Minuteman
Mar 24, 2011
34
0
62
#1
Im sorry this question must have brought up before, but I couldnt find it. I bought a ne M40A3 from GA. Should I break the barrel in?I had never heard about that before. Just want to do the right thing
 
#8
Re: barrel break in

You will have to throw it around a bit until it makes the right harmonic sounds! Then its ready to be shot.

Seriously just shoot it
smile.gif
 
#13
Re: barrel break in

Barrel breakin is a good idea wether it helps or not. The idea is to keep the copper fouling as low as possible while the initial bullets polish up and clear out any burrs in the grooves . If you allow a heavy layer of copper to deposit straight up and the barrel is rough , getting it clean can be a much bigger chore and if you don't get it very clean the barrel may become a quick fouler from then on.
A super smooth match barrel may not get any benifit but a rough barrel might.
My advise is , why not , it can't hurt to give it some extra cleaning at first and it may make a top barrel out of a potentialy bad one.
The extra scrubbing with a bronze brush in a rough barrel could also help in this regard. If you have a select match lapped barrel then you may not want or need to use a metal brush at all in such a bore.
Always remember that the advise from barrel makers is tempered with the need to sell as many barrels as possible and never admit that any such burrs ever exist in any of their barrels.

 
#15
Re: barrel break in

it's just a little extra time and can't hurt. i did my dpms ar 10 24'' ss bull per instructions shoots great dont know if it made a diffrence but it is a tack driver.
 
#16
Re: barrel break in

Although I wouldn't contradict the manufacturer's instructions, for rifles I didn't buy that come with a break in recommendation, I just shoot 'em.

Especially if the rifle has a chrome bore like the TRG22. Expecting a copper bullet jacket to polish a chrome bore is like expecting a chunk of lead to polish an anvil. I suppose it could happen in many years, but it just doesn't make sense to expect a softer medium to polish a harder one.

We use harder things to polish or sharpen tools, just like sharpening stones. I don't sharpen my knife with a bar of copper for a very logical reason.
 
#17
Re: barrel break in

What you are saying is not right . Even the human hand will polish up hard steels with constant rubbing over years .
The copper jacket is not the only thing in the bore .
There is powder fouling which has lots of carbon in it , primer fouling , some have powdered glass in them .
Add to that a soft material like gilding metal to bed into at 3000 fps you have a lapping system , very slow lapping system granted . If it could not polish it at all it could not wear it out either and we know they wear out eventually. Most barrels get replaced before the bore gets obviously worn down because the throat is totally gone and accuracy is suffering . I have seen very old barrels where the rifling was almost gone all the way to the muzzle.
The short duration of barrel break in , if done properly can assist the smoothing out of a barrel from manufacturing burrs and minor inperfections if the copper fouling is not allowed to build up between shots. It can't do what lapping a barrel will do with a cast lap and cutting paste in a short space of time but that is only for major problems or smoothing up a match barrel that is made to allow for lapping to a high finish.
You can hone a knife on a " LEATHER " strop and that is way softer than hardened carbon steel is it not. What is happeneing is the leather strop is fatiguing and polishing away the fine feathered edge ( burrs)left by stoning so it is smoother along its edge. The bullets are doing the same thing in the barrel if no layers of copper fouling is protecting them . Why do you think barrel makers lapp some barrels for fun.

 
#18
Re: barrel break in

REPOST FROM JEFF

I am not the author of this piece, nor am I trying to take credit for writing it. It contains alot of good information in my opinion.
AGAIN I am reposting this for informational purposes, Author JEFF


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 Electrical 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... 99.9% of shooters don’t 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 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?
• 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 ass guess)
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-tometal 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 preburnished 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.
_________________________
Jeff
Distance is not an issue, but the wind can make it interesting!
Mathew 5:16
Top
 
#20
Re: barrel break in

To his, his own. I have followed breakin and not and both rifles shoot 1/2 moa when i did my part. Not sure if either had anything to do with the accuracy or i just had good sticks
 
#21
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chaos27delta</div><div class="ubbcode-body">REPOST FROM JEFF

I am not the author of this piece, nor am I trying to take credit for writing it. It contains alot of good information in my opinion.
AGAIN I am reposting this for informational purposes, Author JEFF


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 Electrical 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... 99.9% of shooters don’t 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 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?
• 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 ass guess)
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-tometal 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 preburnished 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.
_________________________
Jeff
Distance is not an issue, but the wind can make it interesting!
Mathew 5:16
Top </div></div>
A lot of writting and name dropping but no actual proof at all either way. Some of the barrel makers recommend barrel breakin .
So it's still the status quo , do it if you want to , it can't hurt . I know a few people that have a lot of trouble with quick fouling barrels and they don't believe in breaking in a barrel. On the other hand I have seen barrels shoot very well with light fouling problems and not broken in. So there is no definate rule here. It's a personal choice. To say it does not help and is a waste of time is just as wrong as saying it will help in every case .
 
#22
Re: barrel break in

I'd say any breaking in will be done by the bullets. Not but a brush or patch. So shoot the thing you'll know it's broken in when it doesn't need cleaning after every range trip.
 
#24
Re: barrel break in

I have seen barrels get easier to clean with proper break in. There's no doubt in my mind it helps.

Don't use special bullets or hot loads. Regular copper jacketed bullets in front of a mild load is what I like.

Do not use steel brushes ever. I see no need for brass brushes. Some will argue this but Nylon does the job, so why argue. Use Nylon.

Shoot and clean the way GAP says for the first, at least, 5 rounds. 10 or 12 if you've got the patience.

Get ALL the solvent out of the bore and chamber before firing or it could be bad.

Use a damn bore guide! They're $15!

Buy a chamber mop, they're $3.

Use carbon fiber or fiberglass cleaning rods. Never steel.


After break in, don't go nuts cleaning your rifle. I clean every 100 rounds or so after break in. I think its very common for people to damage their throats and barrels by cleaning incorrectly and too often. Its a shame.
 
#28
Re: barrel break in

Just shoot it , you know where I see gun's for sale and the add read's "properly broken in and meticulously maintained " that is sure sign that I will not be buying that gun ,as its owner has probably wrecked the bore .

Just shoot it clean when you notice a drop in accuracy .

That being said you need to have confidence in your rifle so do what makes
you all warm and fuzzy .
 
#30
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Whoshotya</div><div class="ubbcode-body">LonewolfUSMC pretty well sums up a proper match grade barrel break in...
http://www.youtube.com/watch?v=f_LvPjreNjg&feature=player_embedded#at=13 </div></div>

Hahaha... Another great video. If you look down at the comments he states that he later had a world renown bench rest gunsmith come in and scope that very bore. Said it looked great, throat and all LOL... the things people do...
 
#31
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">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).</div></div>

High level view of Sanity Checking 101

Sometimes when people write a lot and drop a lot of names and construct an elaborate Appeal to Authority, to reach a controversial conclusion without actually addressing the question, it's a good idea to check their work. Here's an example:

Let's be generous and assume when "Jeff" said "All of this happens in nanoseconds", he meant all of that happened in say, 100 nanoseconds and not just say, a couple nanoseconds... or 1000 nanoseconds, since if he'd meant 1000 nanoseconds, he probably would have called them "microseconds".

Let's further assume a 24" barrel, since a whole number like 2 feet makes the math easier.

So, if a bullet traverses 2 feet in 100 nanoseconds, how many feet per second (fps) is its velocity?

go ahead, calculate it. I'll wait.


Here's a hint: 100 nanoseconds is .0000001 seconds



My guess is "Jeff" is a little over published max loads
smile.gif
 
#32
Re: barrel break in

Lets see if I have this right.

If the speed of the bullet equals 1 foot in .00000005 seconds, then that also equals 5280 ft (1 mile) in 0.000264 seconds. Bullet speed is 0.000264 seconds per mile. Divide 1 mile by 0.000264 seconds equals 3787.87 miles per second. Which equals 227,272.72 miles per minute and thus equals 13,636,363.63 miles per hour!

with that sort of speed, who gives a shit about wind? You could shoot one hole groups at a mile (or 10 miles or 100 miles) through a Catagory 5 tornado with that kind of velocity!

Can I get that in a semi-auto with a 30 round magazine and a 16 inch barrel?
 
#36
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bpnelson</div><div class="ubbcode-body">Just shoot and clean if there is fouling. </div></div>

Well put!!! If it fouls and you start throwing shots...then clean.
 
#37
Re: barrel break in

To those who "just shoot it", and say fuck it...

You spend $3000+ on a rifle, wait up to 6 months, demand the highest in quality work and components...

But you cant take 45 minutes to follow break-in instructions, just in case it does matter?

Am I positive it matters? No. But I'll spend 45 minutes and a few rounds to do it just in case.

I've seen barrels get easier to clean(meaning copper fouling got easier to remove) during break in. There isnt really any arguing that. And like I just said, even if you dont believe it, you cant take 45 minutes and do it anyways? If you clean your gun right you arent hurting a damn thing doing it during break in. So I ask, why NOT do it??
 
#38
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AZPrecision</div><div class="ubbcode-body">To those who "just shoot it", and say fuck it...

You spend $3000+ on a rifle, wait up to 6 months, demand the highest in quality work and components...

But you cant take 45 minutes to follow break-in instructions, just in case it does matter?

Am I positive it matters? No. But I'll spend 45 minutes and a few rounds to o it just in case. </div></div>

AMEN to that brother! its not like a break-in is some huge endeavor, taking hours upon hours. =)
 
#39
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gale McMillan</div><div class="ubbcode-body">As a barrel maker I have looked in thousands of new and used barrels with a bore scope and I will tell you that if every one followed the prescribed [one shot, one clean] break-in method, a very large number would do more harm than good. The reason you hear of the gain in accuracy is because if you chamber a barrel with a reamer that has a dull throater instead of cutting clean sharp rifling it smears a burr up on the down wind side of the rifling. It takes from one to two hundred rounds to burn this burr out and the rifle to settle down and shoot its best. Any one who chambers rifle barrels has tolerances on how dull to let the reamer get and factories let them go longer than any competent smith would.

Consider this: every round shot in breaking-in a barrel is one round off the life of said rifle barrel. No one has ever told me the physical reason of what happens during break-in firing. In other words what, to the number of pounds of powder shot at any given pressure, is the life of the barrel. No one has ever explained what is being accomplished by shooting and cleaning in any prescribed method. Start your barrel off with 5 rounds and clean it thoroughly and do it again. Nev Maden, a friend down under that my brother taught to make barrels was the one who came up with the [one shot one clean] break-in method. He may think he has come upon something, or he has come up with another way to sell barrels. I feel that the first shot out of a barrel is its best and every one after that deteriorates [the bore] until the barrel is gone. If some one can explain what physically takes place during break-in to modify the barrel then I may change my mind. As the physical properties of a barrel don't change because of the break-in procedures it means it's all hog wash. I am open to any suggestions that can be documented otherwise if it is just someone's opinion--forget it.</div></div>

This is the way i look at it. I'm not simply saying "fuck it" it's more along the lines of how is running a cleaning patch with solvent through the barrel shot after shot going to change anything, or for lack of a better word alter the barrel to shoot better.
 
#40
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Blackops_2</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gale McMillan</div><div class="ubbcode-body">As a barrel maker I have looked in thousands of new and used barrels with a bore scope and I will tell you that if every one followed the prescribed [one shot, one clean] break-in method, a very large number would do more harm than good. The reason you hear of the gain in accuracy is because if you chamber a barrel with a reamer that has a dull throater instead of cutting clean sharp rifling it smears a burr up on the down wind side of the rifling. It takes from one to two hundred rounds to burn this burr out and the rifle to settle down and shoot its best. Any one who chambers rifle barrels has tolerances on how dull to let the reamer get and factories let them go longer than any competent smith would.

Consider this: every round shot in breaking-in a barrel is one round off the life of said rifle barrel. No one has ever told me the physical reason of what happens during break-in firing. In other words what, to the number of pounds of powder shot at any given pressure, is the life of the barrel. No one has ever explained what is being accomplished by shooting and cleaning in any prescribed method. Start your barrel off with 5 rounds and clean it thoroughly and do it again. Nev Maden, a friend down under that my brother taught to make barrels was the one who came up with the [one shot one clean] break-in method. He may think he has come upon something, or he has come up with another way to sell barrels. I feel that the first shot out of a barrel is its best and every one after that deteriorates [the bore] until the barrel is gone. If some one can explain what physically takes place during break-in to modify the barrel then I may change my mind. As the physical properties of a barrel don't change because of the break-in procedures it means it's all hog wash. I am open to any suggestions that can be documented otherwise if it is just someone's opinion--forget it.</div></div>

This is the way i look at it. I'm not simply saying "fuck it" it's more along the lines of how is running a cleaning patch with solvent through the barrel shot after shot going to change anything, or for lack of a better word alter the barrel to shoot better. </div></div>


You arent just running a patch through it. Do you understand what break-in is? It reduces copper fouling and may help the throat smoothen out. It isnt a cure all for a shitty reamer or shitty barrel. It simple helps reduce copper fouling.

And the life of your barrel? You're worried about 10 rounds? If you're worried about 10 rounds of barrel life being given away, I assume every rifle you own is a 308...



I KNOW people will argue this all year, and I KNOW some of you wont do it no matter what, fine.
But its 10 rounds, and 45 minutes max of your time. If you cant give up 10 rounds and 45 minutes then I dont have much faith in your patience as a shooter/rifle owner.
 
#41
Re: barrel break in

Yes i realize it reduces copper fouling, but i don't feel it's necessary because i'm not going to clean the bore every shot after shot. As i'm going to clean it after i get done shooting. I did it with my 5R everything has worked out fine.

Your right it doesn't take much time, but it's also a matter of preference.
 
#46
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AZPrecision</div><div class="ubbcode-body">You only clean after every shot for 5-10 rounds. Then you can do whatever you want. I only clean about every 100 rounds, after break in.

To each their own </div></div>

Have you ever not broken in one of your own barrels?

I tried a break-in on my first custom rifle about ten tears ago. It had a Krieger barrel. That process took a hell of a lot longer than 45 minutes. It was many hours spent cleaning to bare metal between shots, then between three shot stings, then five shot strings. The people I see at the range doing it are burning most of the day cleanaing, especially when it is a factory rifle.

What i know now is every custom i have owned since, cleans up just fine after the first range session(no break-in). In my personal experience, that includes barrels from Lilja, Brux, Krieger, Bartlein, Shilen, Broughton, and Rock. 3 groove, four groove, 5R and 5C rifling. Some are faster or slower than expected, but they have all acted the same with regards to cleaning/accuracy.
 
#47
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">If I can't see any difference in the barrel and I can't see any difference on paper.....where should I see the difference?

I prefer economy of motion. </div></div>

The difference can be seen in cleaning during break in.

I think its safe to say some barrel will benefit less from doing it. Example would be Shilen's select match barrels. When we broke in the last one, it seemed to be "broken in" in just 5 rounds. Saw no reason to continue cleaning every shot, and went ahead and fired a group. Then cleaned one more time, because why not.

I never clean without a bore guide. I'm aware of what solvents to use and how to correctly use then. I only use Nylon brushes. And I use jags correctly. Point is, I dont hurt barrels when I clean. No reason not to "break in"
 
#48
Re: barrel break in

i think this horse has been beat down to bare bones. to each thier own, if you feel it does, or it might, make a difference, and you can clean a bore without damaging it, go ahead and do a break in. if you don't think it makes a difference, then don't do it. i don't think it does, but i also believe, over time, those rough spots in a bore will smooth themselves out. we use 2 methods to check our bores, and niether is by how many patches it takes before you stop seeing copper. the first is a borescope, which most shooters may not have access to. the second is something any of us can do.

we take 2 brass rods, one short, one a little longer than the barrel and a cast lead bullet. use the long rod to push the bullet from the chamber towards the muzzle, then take the other shorter rod and with a light tap from a hammer smash the cast bullet. now use the longer rod the run the bullet up and down the bore, feeling for spots that are tighter or looser than the majority of the bore. if the bore has to much of a change, it gets hand lapped, if not, it gets shot.
 
#49
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Blackops_2</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gale McMillan</div><div class="ubbcode-body">As a barrel maker I have looked in thousands of new and used barrels with a bore scope and I will tell you that if every one followed the prescribed [one shot, one clean] break-in method, a very large number would do more harm than good. The reason you hear of the gain in accuracy is because if you chamber a barrel with a reamer that has a dull throater instead of cutting clean sharp rifling it smears a burr up on the down wind side of the rifling. It takes from one to two hundred rounds to burn this burr out and the rifle to settle down and shoot its best. Any one who chambers rifle barrels has tolerances on how dull to let the reamer get and factories let them go longer than any competent smith would.

Consider this: every round shot in breaking-in a barrel is one round off the life of said rifle barrel. No one has ever told me the physical reason of what happens during break-in firing. In other words what, to the number of pounds of powder shot at any given pressure, is the life of the barrel. No one has ever explained what is being accomplished by shooting and cleaning in any prescribed method. Start your barrel off with 5 rounds and clean it thoroughly and do it again. Nev Maden, a friend down under that my brother taught to make barrels was the one who came up with the [one shot one clean] break-in method. He may think he has come upon something, or he has come up with another way to sell barrels. I feel that the first shot out of a barrel is its best and every one after that deteriorates [the bore] until the barrel is gone. If some one can explain what physically takes place during break-in to modify the barrel then I may change my mind. As the physical properties of a barrel don't change because of the break-in procedures it means it's all hog wash. I am open to any suggestions that can be documented otherwise if it is just someone's opinion--forget it.</div></div>

This is the way i look at it. I'm not simply saying "fuck it" it's more along the lines of how is running a cleaning patch with solvent through the barrel shot after shot going to change anything, or for lack of a better word alter the barrel to shoot better. </div></div>

^^^Amen.

I push a patch with BBS through a new barrel (good barrels of course), then a dry patch. Then I shoot about 400-600 rounds (depending on caliber) in field conditions. Then I clean and repeat.
 
#50
Re: barrel break in

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AZPrecision</div><div class="ubbcode-body">You only clean after every shot for 5-10 rounds. Then you can do whatever you want. I only clean about every 100 rounds, after break in.

To each their own </div></div>
I'm with AZ on this one... i'm usually running out of copper fouling after cleaning between rounds, in about 7-9 shots, then its go time... and barrel break in does make a big difference when cleaning time comes...IMHO.
 
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