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Barrel break in

Morning everyone after so thoughts from you all as to barrel break in I'm about to take delivery of a 6mm BR which needs breaking in
I have two hundred new cases and the same twice fired cases
Having measured all the fired cases I've found around forty that were under 1.55 CIP spec and have trimmed these down to the shortest would these be suitable for breaking in the barrel or would you all use new cases
Bey and all advice greatly appreciated
Steve
 
Oh boy here we go. Many will disagree, but I'm of the opinion that barrel break in with a top custom barrel is a waste of barrel life, components, and time. Just make sure it is clean before the first shot. However, my last new barrel was a Barlein and I did use their recommended process since it took very little effort. I've pasted it from their website below:

"Shoot one round and clean for the first two rounds individually. Look to see what the barrel is telling you. If I’m getting little to no copper out of it, I sit down and shoot the gun. Say 4 – 5 round groups and then clean. If the barrel cleans easily and shoots well, we consider it done."

You're gonna love the 6BR.
 
I follow the directions by Krieger on all my premium barrels. I shoot for groups, just clean more until the barrel tells me I don't need to. Normally I go shoot 1, clean for about 5 shots, then shoot 2 clean, shoot 3 clean, shoot 4 clean, then shoot 5 clean. At that point I'm done. And all I have done is cleaned an extra 8 times (9 instead of 1).

Their words:

"BREAK-IN & CLEANING:​

With any premium barrel that has been finish lapped -- such as your Krieger Barrel --, the lay or direction of the finish is in the direction of the bullet travel, so fouling is minimal compared to a barrel with internal tooling marks. This is true of any properly finish-lapped barrel regardless of how it is rifled. If it is not finish-lapped, there will be reamer marks left in the bore that are directly across the direction of the bullet travel. This occurs even in a button-rifled barrel as the button cannot completely iron out these reamer marks.
Because the lay of the finish is in the direction of the bullet travel, very little is done to the bore during break-in, but the throat is another story. When your barrel is chambered, by necessity there are reamer marks left in the throat that are across the lands, i.e. across the direction of the bullet travel. In a new barrel they are very distinct; much like the teeth on a very fine file.
When the bullet is forced into the throat, copper dust is removed from the jacket material and released into the gas which at this temperature and pressure is actually a plasma. The copper dust is vaporized in this plasma and is carried down the barrel. As the gas expands and cools, the copper comes out of suspension and is deposited in the bore. This makes it appear as if the source of the fouling is the bore when it is actually for the most part the new throat.
If this copper is allowed to stay in the bore, and subsequent bullets and deposits are fired over it, copper which adheres well to itself, will build up quickly and may be difficult to remove later. So when we break in a barrel, our goal is to get the throat “polished without allowing copper to build up in the bore. This is the reasoning for the fire-one-shot-and-clean procedure.
Every barrel will vary slightly in how many rounds they take to break in For example a chrome moly barrel may take longer to break in than stainless steel because it is more abrasion resistant even though it is a similar hardness. Also chrome moly has a little more of an affinity for copper than stainless steel so it will usually show a little more color if you are using a chemical cleaner. Rim Fire barrels can take an extremely long time to break in, sometimes requiring several hundred rounds or more. But cleaning can be lengthened to every 25-50 rounds. The break-in procedure and the cleaning procedure are really the same except for the frequency. Remember the goal is to get or keep the barrel clean while breaking in the throat with bullets being fired over it.
Finally, the best way to tell if the barrel is broken in is to observe the patches; i.e. when the fouling is reduced. This is better than some set number of cycles of shoot and clean as many owners report practically no fouling after the first few shots, and more break-in would be pointless. Conversely, if more is required, a set number would not address that either. Besides, cleaning is not a completely benign procedure so it should be done carefully and no more than necessary."

 
I must be missing something....possibly the true definition of "barrel break in", because I don't see the significance of the cases. It is my understanding and practice that barrel break in is firing the rifle until it stops coppering up.
What I have found to be the number one thing when doing this {still guessing we are talking about the same thing here...} is that the bore be completely devoid of any copper when you fire it. The only time any actual "break in" is really happening is when a bullet passes thru a completely whistle clean bore. Passing a bullet over a bunch of copper already there just deposits more and does zero for break in.
As long as the brass is sized and headspaced to safely fire in the rifle I don't see how anything regarding the brass matters to barrel break in {at least as I understand it}.
It is definitely not a waste of time if it needs it and is coppering. Now, I will agree and say that a barrel in a hot caliber that coppers up bad can be a waste of time because by the time you get it to stop copper fouling the throat is shot out....ask me how I know this one.

Edit: although you can do without one, this is one time when a borescope is your friend. You can pretty readily tell if it's a rough throat, as suggested above, or the bore itself. Heavy deposits smeared on the lands with little in the grooves doesn't happen because of the throat.
 
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Oh boy here we go. Many will disagree, but I'm of the opinion that barrel break in with a top custom barrel is a waste of barrel life, components, and time. Just make sure it is clean before the first shot. However, my last new barrel was a Barlein and I did use their recommended process since it took very little effort. I've pasted it from their website below:

"Shoot one round and clean for the first two rounds individually. Look to see what the barrel is telling you. If I’m getting little to no copper out of it, I sit down and shoot the gun. Say 4 – 5 round groups and then clean. If the barrel cleans easily and shoots well, we consider it done."

You're gonna love the 6BR.
Read both pros and cons. Attached is an article from sniper country on the subject.


Barrel break in


11 March 2004


By A poster on the site Texas Predator Posse


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I've spent the last few months trying to get a better understanding of what a barrel break-in process is and how to properly clean a rifle. What to do and what not to do.


I've spent a lot of time on this board, the BR board and other shooting boards listening to members and what works for them. Conclusion, what works for some, doesn't work for others. Being an engineer in the telecommunications field, when it's broke or you don't understand something you go back to manufactures specs and schematics. So that's kinda what I did on this subject.


I've talked with 4 metallurgist and 3 barrel manufactures (Rock Creek, Hart and Shilen), on the subject. From a scientific point of view, they all said and agreed to pretty much the same thing.


First, barrel break-in processes keep them in business. This shoot and clean, shoot and clean every round or few rounds break-in process only damages your brand new match barrel. Think of a car engine for a moment. Why do we use oil in the engine? To prevent metal-to-metal contact and reduce friction between two metal surfaces. Your barrel is no different from the engine. Mike Rock at Rock Creek barrels gave me the most detailed explanations on barrels and ballistics. Mike has his degree in metallurgy; he was also the chief ballistics engineer for the Army for many years at the Aberdeen Proving grounds. Stan Rivenbark was one of the top ballistic engineers for Raytheon before he retired in the 70's and also has a degree in metallurgy. I also talked with two local metallurgists here in North TX. I confirmed my findings with each person to see if they agreed or disagreed. Conclusion, they all agreed with each other's assessments.


When Mike worked at Aberdeen proving grounds, the Army used high speed bore videos with mirrors, thermal imaging and computers to analyze any and everything that happens when the firing pin hits the primer and the round goes off. When the primer ignites there is enough pressure to move the bullet forward into the lands. The bullet then 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 out the barrel. All of this happens in nanoseconds (billionths of a second). Your bullet starts and stops at least twice and sometimes three times before it leaves the barrel. This is fact.


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 sheer away layers of metal from each surface. So if your bullet is starting and stopping two or three times as it leaves the barrel, that's two or three places for metal-to-metal contact to happen as well as the rest of your bore. The use of JB's and Flitz can and will take you down to metal-to-metal contact. For all intents and purposes, JB's and Flitz are not the most ideal products for cleaning your rifle.


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. Shilen, Hart and Rock Creek will all void your barrel warranty if you shoot moly bullets and for good reason. This is not to say that moly is necessarily bad for a barrel, but it is when applied to bullets. There is no way possible to coat a bore with moly bullets. The bullet contact surface in the barrel is only so big. But when your round goes off, moly comes off the contact surface of the bullet in the throat area of the rifle and is bonded to the barrel due to the excessive heat and pressure. We're not talking coated or adhered to, we're talking bonded, d**n near permanent. With this, some of the jacket coating comes off the bullet. Follow this up with another round and you've now embedded the copper jacket between layers of bonded moly. This is the beginning of the black moly ring, which ruins countless barrels and is so hard; it can hardly be scraped off with a screwdriver's corner edge. This is what happened to a new Shilen SS select match barrel I had to have replaced with less than 400 rounds through it. I can't talk for Fastex as I don't or none of the folks I talked to knew enough about the product to comment on it. When I talked to Mike about my new barrel and the barrel break-in process, this is what he had to say. He first hand laps each barrel with a lead lap. He then uses two products from Sentry Solutions, a product called Smooth Coat, which is an alcohol and moly based product. He applies wet patches of Smooth Coats 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 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 or so 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.


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 regimen of cleaning and if you have to use JB's or flitz type products, go very easy with them, or better yet avoid them. Never clean down to bare metal. 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.


Well that's the long and skinny from the scientific point of view on the subject. If you're ever in doubt about the real condition of your barrel, take it to someone who has a bore scope and even better if someone has a bore scope that can magnify the view. You may be surprised at what is really going on in your barrel.


I'm sure this will spark a debate here and there, but that's good thing. The more information we have, the better off we'll be.
 
As I had an Ackley chamber, I used Trail boss powder to break in and fire form the cases. I used this powder because of less heat generated by it. Cleaning after one round for the first five rounds. Then I used an Enduron powder, IMR 4451, to try to reduce copper fowling. Was told that those Enduron powders change the copper to a black residue that looks like carbon but is still copper in disguise. Do not have a bore scope so I can not be sure if this worked or not.
 
I have followed the various directions for hand lapped barrels for years. Sometimes they seemed to work, sometimes not so much. Started several years ago, 3 shots cleaning between each shot, end of break in. Start normal group development. Has worked well for me.Why waste rounds during the competitive life of a barrel. Makes no sense to me. I expect to get to back to back 3 shot groups in zeros or low ones then get 5 shot back to back groups in low .1s or better. All initial development with 2 shot groups. Verify back to back 2 days, ready for competition. Any change after this as rounds mount is with tuner which until this point has not been adjusted. At about 1500 rounds I sometimes will play with seating depth if barrel seems to be losing its competitive edge.This is with 6BRX and 6 PPC. There is more than one way to achieve good results, come up with a system and stick to it if it works for YOU.
 
The only thing more debated by the experts on this board then barrel break-in is barrel cleaning.

I have had more then my share of match barrels of various manufacturer over the years and all of them broke in fine and lasted their expected life span, except one Hart 308, which although looked pretty good, would just barely hold a 10 ring on a LR F Class target, no matter what I fed it.

All that being said, my goal is to smooth out the tips of the lands and tool marks to the point that I can get a good read on setting my bullet jump. (Which will always change as rounds go down, but you’ve got to start somewhere).

First, I will borescope it, looking for defects and to get the lay of the land, I will shoot and clean for 5 rounds, do a couple of 3 round groups, clean between them, followed by a couple shoot and clean 5 round groups. Done. Clean it well, borescope it to recheck it for stupid stuff you didn’t anticipate, take some measurements and start load development.
One manufacturer of an AR match barrel told me to just go out and shoot it and clean it when I was done for break in, that coming from a well know and respected gunsmith.

Search for the “Cleaning” article in the forum, lots and lots of well know barrel makers, each with their own spin on how to clean. Same with break in, pick one if it works and the barrel performs and lasts a normal life, you’re there, don‘t over think it.
 
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I start with a clean barrel and fire one shot and patch it out, shoot another shot and patch it out and continue until I don't get copper on the patch. This is usually between 6 and 8 shots with a Kreiger barrel.

I read about this method someplace, a high end barrel maker, a known BR shooter, I don't remember. I also use these shots to sight the rifle.
 
Wow I really stirred a hornet's nest with this one
Thanks guys to the very informative posts and replies
I have a Bore scope I will take it along once I start to shoot and be guided as to the amount of copper build up I find
I'll keep you all posted
Steve
 
I have followed the various directions for hand lapped barrels for years. Sometimes they seemed to work, sometimes not so much. Started several years ago, 3 shots cleaning between each shot, end of break in. Start normal group development. Has worked well for me.Why waste rounds during the competitive life of a barrel. Makes no sense to me. I expect to get to back to back 3 shot groups in zeros or low ones then get 5 shot back to back groups in low .1s or better. All initial development with 2 shot groups. Verify back to back 2 days, ready for competition. Any change after this as rounds mount is with tuner which until this point has not been adjusted. At about 1500 rounds I sometimes will play with seating depth if barrel seems to be losing its competitive edge.This is with 6BRX and 6 PPC. There is more than one way to achieve good results, come up with a system and stick to it if it works for YOU.
This, and I think I remember reading an article by Gale McMillan and I think, according to him, barrel break in was a waste of barrel life.
Jonathan Taylor
 
When it was time to change my stock barrel , I had my rifle completely blueprinted and bedded . The barrel l went with is a Rock Creek M24 5R , my break in was my normal shooting , 20 rounds with a cooling down between shots , cleaning a match grade barrel hardly ever has copper build up , mostly carbon . KG -1 and old reliable #9 works well for me , only a few patches and it's clean .
 
Oh boy here we go. Many will disagree, but I'm of the opinion that barrel break in with a top custom barrel is a waste of barrel life, components, and time. Just make sure it is clean before the first shot. However, my last new barrel was a Barlein and I did use their recommended process since it took very little effort. I've pasted it from their website below:

"Shoot one round and clean for the first two rounds individually. Look to see what the barrel is telling you. If I’m getting little to no copper out of it, I sit down and shoot the gun. Say 4 – 5 round groups and then clean. If the barrel cleans easily and shoots well, we consider it done."

You're gonna love the 6BR.
No flack from me. Break in of a premium barrel is a waste of supplies.
 
I used to shoot with a couple of guys that shot in several of the bigger bench rest matches and several 1000 yard matches as well. They both said start with a thoroughly clean barrel, then fire one shot and thoroughly clean the barrel again. Do this for three cycles and then go to two shots and thoroughly clean the barrel again. Do this for three cycles and if needed go to three shot cycles thoroughly cleaning between cycles. When you stop getting copper on your cleaning patches, the barrel is seasoned and broken in. I followed this advice with two Douglas barrels and one Kreiger. The Kreiger stopped showing copper after the fifth shot, the Douglas barrels went seven and nine shots until they stopped showing copper on the patches.
 
6mm Tubb barrel break in kit. 15 shots at reduced charge. Clean the barrel. Done.

Or you can shoot 100-150 and wait until the it stops speeding up.
 

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