You can't prevent a barrel from breaking in. If you shoot it, it will break in. The sharpness of the throat is important to accuracy. I prefer jb to iosso as its less aggressive, but use it only when you have to. Montana extreme copper killer with a bronze brush should keep you off the jb for many hundreds of rounds. Yes, Iosso in the throat does shorten the accuracy life of a barrel. You do not want to smooth out the rifling. I know this as a fact.
Interesting post from Gale MCMillan regarding how the "barrel break in" process got started
How to Break-in a Barrel
-- A Dissenting Point of View
Gale McMillan, of McMillan Stocks fame, was one of the finest barrel-makers and benchrest shooters of all time. Here he argues that elaborate barrel break-in procedures do more harm than good.
Comments collected from Gale's Gun Forum postings.
"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.
Another tidbit to consider--take a 300 Win Mag that has a life expectancy of 1000 rounds. Use 10% of it up with your break-in procedure. For every 10 barrels the barrel-maker makes he has to make one more just to take care of the break-in. No wonder barrel-makers like to see this. Now when you flame me on this please [explain] what you think is happening to the inside of your barrel during the break in that is helping you.
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.
It all got started when a barrel maker that I know started putting break-in instructions in the box with each barrel he shipped a few years ago. I asked him how he figured it would help and his reply was if they shoot 100 rounds breaking in this barrel that's total life is 3000 rounds and I make 1000 barrels a year just figure how many more barrels I will get to make. He had a point; it definately will shorten the barrel life. I have been a barrel maker a fair amount of time and my barrels have set and reset benchrest world records so many times I quit keeping track (at one time they held 7 at one time) along with High Power, Silhouette, Smallbore national and world records and my instructions were to clean as often as possible preferably every 10 rounds. I inspect every barrel taken off and every new barrel before it is shipped with a bore scope and I will tell you all that I see far more barrels ruined by cleaning rods than I see worn out from normal wear and tear. I am even reading about people recommending breaking-in pistols. As if it will help their shooting abilip
I can only speak from experience with the last 10 or so new barrels. With the proper chronograph, they have all sped up in speed by 100-130 fps in the first 100+ rounds. This was tested by a lab radar. I feel if I can settle the speed in 60 or so rounds by breaking in the barrel aren't you saving rounds.
X-2I suppose if you feel that process works for you. Barrel wear is barrel wear. Personally I'd rather break mine in with bullets and not excelerate the process with over cleaning.
Only thing I ever saw an improvement on after a "break in" was it seemed to clean easier / faster. I typically don't clean until around 250 Rds or so, dependent on when e accuracy starts to deteriorate and then clean before that.
Made zero difference in accuracy. They (Bartlien / Kreigers) hammered from the first round to the last. I haven't broke a barrel
in with a cleaning rod and patches in 10+ years.
Looked for DBC in a Midway search and got "No Results"?this is the simple way to break in a new barrel 1st run a couple of patches with wipe - out on patches in barrel ,2nd run 2 dry patches tru barrel ,now apply DBC as directions say . you can buy DBC from Midway USA . i do this to all my rifles before i shoot them now. on the 24 HR. Campfire site on the forum ask the gun writers Mule Deer explains the whys. once that`s done just shot your rifle i never clean mine for 100-200 shot rounds.
I posted this elsewhere in an existing discussion thread but I think it would be helpful to have as a stand alone contribution to the subject. Keep in mind, if you ask 100 barrel makers or rifle builders for their advice on the subject, you'll get many opinions. This is just mine based on lots of study and on my own rifle and shooting experience.
*************************************************************
Here is my take on the subject...and what I give my rifle customers as advice. This is for hand lapped, match grade barrels, not factory gun barrels.
Long Range Rifles, LLC
Cleaning Instructions
Cleaning Equipment:
Dewey one-piece cleaning rods, jags and brushes are recognized throughout the industry as the very best. I recommend and use them. A properly fitted bore guide is a must and there are many good ones available such as the Tipton Universal bore guide. Bore Tech Eliminator is a non-ammonia copper solvent that we also use for its fast effective copper removal. Under certain conditions ammonia based cleaners can harm a rifle's bore. So we do not recommend their use. Iosso Bore Paste is the only abrasive paste we recommend, and it is for the specific occasional use of removing a carbon build-up in your barrel. Like any abrasive, over-use will damage your barrel. So read more about its use in the general cleaning section below.
Barrel Break-in:
We know that a custom barrel like the Brux Barrels we use at Long Range Rifles break-in faster than factory/production barrels. So what exactly is a broken-in barrel? A barrel is broken-in at the point where it has obtained its maximum accuracy, minimum copper fouling and stabilized velocity readings.
The process of break-in is initiated by shooting just 3-5 rounds and then cleaning your rifle's barrel to remove the copper fouling. Normally repeating this step 2-3 more times will complete the process of reducing copper fouling. During this process, you will notice the barrel is cleaning much easier at every step. With 3-4 cleanings after 3-5 rounds each in the first 25 rounds, go ahead and use the rifle normally, as this part of break-in is complete.
Do not use any abrasive paste type cleaners during break-in as doing this can damage your rifle's bore.
Regarding the aspect of stabilizing velocities, the use of chronographs and experience will show that the barrels tend to speed up over the first 50 to 100 or so rounds, with the exact same load being used during that time period. What does this mean to the average marksman? First understand that your rifle's long range trajectories will change slightly at some point during the first 50-100 rounds. Second, if you're doing load development early on in the barrel's life, (less than 50 rounds) don't max out your pressure or velocity. You may be well over pressure when you hit the 100+ rounds fired mark, caused by a possible velocity increase of up to 75 fps.
At the 75 to 100 round mark, your barrel will now be ready for its first general cleaning.
General Cleaning and Maintenance:
Regular cleaning and maintenance will keep your rifle running its best. This outline is by no means the only way to maintain a rifle. But if you are unfamiliar with the process, this is a good outline to guide you in the right direction.
Make sure your Firearm is unloaded before cleaning.
In general, keep your rifle free of dust and grit build up. Simply wipe off the bolt and swab out the receiver with cloths and q-tips, using a commercial gun cleaner designed for general grime. Similarly, wipe down the outside of your firearm as well. Compressed air also works well for removing dust and debris. Inspect and clean your bolt face with solvent and q-tips, paying particular attention to removing any brass flakes or debris build up around the ejector and extractor. Light oil on a hand towel works great for wiping down your rifle and keeping it looking new. Keep your bolt lugs lubed with a small amount of bolt grease such as TM Ultra and Montana X-Treme. This will help keep the rifle well lubed and prevent bolt lug galling.
Rifle bore cleaning is necessary to keep your rifle shooting accurately. Each cartridge designated rifle may require different cleaning intervals depending on such things as: bullet bearing surface length, bullet velocity, over-bore capacity, cleanliness of propellant used, rate of fire, etc. Normally, experience has shown that anywhere from 100 to 300 rounds are within reason for the frequency of cleanings. Cartridges like the 308 Winchester can go as high as 500 under certain circumstances. Always clean from breach to muzzle.
For general bore cleanings, remove your rifle's bolt and insert a bore guide through your rifle's receiver. Using a properly sized jag covered with a patch, apply Bore Tech Eliminator to the patch and push it through the bore. Always clean from breach to muzzle. This will soften up the majority of bore fouling. Follow this up by running a properly sized bronze or nylon brush through a wet bore for 5-6 stokes. This will help to loosen up stubborn copper and carbon fouling. (Recently I switched to nylon brushes since bronze brushes can give you false positives on the presence of copper fouling.) Continue with more wet patches of Bore Tech Eliminator once every 5 minutes, until your patches come out clean, or with just a faint tint of blue. Usually only two or three wet patches sessions is needed.
Once you are satisfied your bore is free of copper fouling, dry out the bore with some clean patches. If you wish, you can run a wet patch of oil thru the bore, followed by a dry patch to remove the excess oil. This is also a good idea if you plan on storing the gun for a period of time before shooting it again. Make sure you swab out your chamber. I use a bore swab such as the one included in the inexpensive Tipton Action and Chamber Cleaning Kit. It includes a chamber swab and a lug recess cleaning tool. Applying a small dab of quality grease (such as TM Ultra or Montana X-Treme) to your bolt lugs after every cleaning to help to prevent bolt lug galling.
Never fire your rifle without first running a dry patch down your bore to insure you have no bore obstructions, or excessive oil in your barrel.
I always fire two "fouling shots" before I hunt with a recently cleaned barrel – or rely on a shot for sighting in. You will note that the point of impact may be off as much as ½ inch at 100 yards within the first two shots.
Persistent Carbon Fouling
At about every 300-500 rounds fired, we recommend cleaning out any carbon build up in your bore. This can be seen with a bore scope, if available. Or this may be needed if you have an unexplained degradation of accuracy. Carbon typically builds up in the first 1-12 inches of your bore. So this is the area that must be cleaned.
First, clean your barrel with the above outlined procedure for a general bore cleaning, to remove copper fouling. Now we can begin to remove the carbon build up. Iosso Bore Paste may be the most effective way available to remove carbon build up. Iosso Bore Paste is a mild abrasive paste. Coat a patch with a layer of paste, and using a jag and bore guide, push the jag into the first 6 inches of bore, from the chamber end, and stroke the area 3-4 times back and forth. Then stroke out to 12 inches 2-3 times, working back and forth from chamber to 12 inches out.
Lastly, push the patch all the way out the barrel with no back and forth strokes past the 12 inch mark. The patch will be black. This is a reaction with the paste and barrel steel. Don't assume you need to repeat this procedure. Doing it just once has proven to remove 90% of carbon fouling. Now using bore cleaner and jagged patches, push a multitude of patches wet and dry through the bore to remove any and all remaining paste, and once again swab out the chamber.
Over-use of any abrasive in a custom barrel will damage the bore, so follow these instructions carefully and do not overuse.
Firing pin and internal bolt cleaning is best accomplished by a certified gunsmith, special tools may be required for the removal of the firing pin assembly from the bolt. All Long Range Rifles are properly lubed at the shop. If you experience problems with your rifle's bolt and firing pin assembly or have exposed your rifles bolt to excessive dirt, grit or water, have your bolt internals cleaned and lubricated immediately.
Trigger cleaning is normally accomplished by removing the barreled action and spraying lighter fluid or alcohol into the mechanism and then blowing dry with compressed air. Using oil in a trigger can cause a buildup of dust and sludge leading to a possible malfunction. Keep your triggers clean and dry for best results.
Muzzle Brake Cleaning
Carbon build up in a muzzle brake can cause a degradation of accuracy when the buildup gets heavy. Clean your brakes at regular intervals. If you feel a muzzle accessory is causing an accuracy issue, remove it and test fire your gun to eliminate it as a possible source. Soaking and brushing seem to be the preferred method of brake cleaning.
Be careful not to damage your rifle's crown when cleaning muzzle accessories.
Long Range Rifles, LLC
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.
Thank youI posted this elsewhere in an existing discussion thread but I think it would be helpful to have as a stand alone contribution to the subject. Keep in mind, if you ask 100 barrel makers or rifle builders for their advice on the subject, you'll get many opinions. This is just mine based on lots of study and on my own rifle and shooting experience.
*************************************************************
Here is my take on the subject...and what I give my rifle customers as advice. This is for hand lapped, match grade barrels, not factory gun barrels.
Long Range Rifles, LLC
Cleaning Instructions
Cleaning Equipment:
Dewey one-piece cleaning rods, jags and brushes are recognized throughout the industry as the very best. I recommend and use them. A properly fitted bore guide is a must and there are many good ones available such as the Tipton Universal bore guide. Bore Tech Eliminator is a non-ammonia copper solvent that we also use for its fast effective copper removal. Under certain conditions ammonia based cleaners can harm a rifle's bore. So we do not recommend their use. Iosso Bore Paste is the only abrasive paste we recommend, and it is for the specific occasional use of removing a carbon build-up in your barrel. Like any abrasive, over-use will damage your barrel. So read more about its use in the general cleaning section below.
Barrel Break-in:
We know that a custom barrel like the Brux Barrels we use at Long Range Rifles break-in faster than factory/production barrels. So what exactly is a broken-in barrel? A barrel is broken-in at the point where it has obtained its maximum accuracy, minimum copper fouling and stabilized velocity readings.
The process of break-in is initiated by shooting just 3-5 rounds and then cleaning your rifle's barrel to remove the copper fouling. Normally repeating this step 2-3 more times will complete the process of reducing copper fouling. During this process, you will notice the barrel is cleaning much easier at every step. With 3-4 cleanings after 3-5 rounds each in the first 25 rounds, go ahead and use the rifle normally, as this part of break-in is complete.
Do not use any abrasive paste type cleaners during break-in as doing this can damage your rifle's bore.
Regarding the aspect of stabilizing velocities, the use of chronographs and experience will show that the barrels tend to speed up over the first 50 to 100 or so rounds, with the exact same load being used during that time period. What does this mean to the average marksman? First understand that your rifle's long range trajectories will change slightly at some point during the first 50-100 rounds. Second, if you're doing load development early on in the barrel's life, (less than 50 rounds) don't max out your pressure or velocity. You may be well over pressure when you hit the 100+ rounds fired mark, caused by a possible velocity increase of up to 75 fps.
At the 75 to 100 round mark, your barrel will now be ready for its first general cleaning.
General Cleaning and Maintenance:
Regular cleaning and maintenance will keep your rifle running its best. This outline is by no means the only way to maintain a rifle. But if you are unfamiliar with the process, this is a good outline to guide you in the right direction.
Make sure your Firearm is unloaded before cleaning.
In general, keep your rifle free of dust and grit build up. Simply wipe off the bolt and swab out the receiver with cloths and q-tips, using a commercial gun cleaner designed for general grime. Similarly, wipe down the outside of your firearm as well. Compressed air also works well for removing dust and debris. Inspect and clean your bolt face with solvent and q-tips, paying particular attention to removing any brass flakes or debris build up around the ejector and extractor. Light oil on a hand towel works great for wiping down your rifle and keeping it looking new. Keep your bolt lugs lubed with a small amount of bolt grease such as TM Ultra and Montana X-Treme. This will help keep the rifle well lubed and prevent bolt lug galling.
Rifle bore cleaning is necessary to keep your rifle shooting accurately. Each cartridge designated rifle may require different cleaning intervals depending on such things as: bullet bearing surface length, bullet velocity, over-bore capacity, cleanliness of propellant used, rate of fire, etc. Normally, experience has shown that anywhere from 100 to 300 rounds are within reason for the frequency of cleanings. Cartridges like the 308 Winchester can go as high as 500 under certain circumstances. Always clean from breach to muzzle.
For general bore cleanings, remove your rifle's bolt and insert a bore guide through your rifle's receiver. Using a properly sized jag covered with a patch, apply Bore Tech Eliminator to the patch and push it through the bore. Always clean from breach to muzzle. This will soften up the majority of bore fouling. Follow this up by running a properly sized bronze or nylon brush through a wet bore for 5-6 stokes. This will help to loosen up stubborn copper and carbon fouling. (Recently I switched to nylon brushes since bronze brushes can give you false positives on the presence of copper fouling.) Continue with more wet patches of Bore Tech Eliminator once every 5 minutes, until your patches come out clean, or with just a faint tint of blue. Usually only two or three wet patches sessions is needed.
Once you are satisfied your bore is free of copper fouling, dry out the bore with some clean patches. If you wish, you can run a wet patch of oil thru the bore, followed by a dry patch to remove the excess oil. This is also a good idea if you plan on storing the gun for a period of time before shooting it again. Make sure you swab out your chamber. I use a bore swab such as the one included in the inexpensive Tipton Action and Chamber Cleaning Kit. It includes a chamber swab and a lug recess cleaning tool. Applying a small dab of quality grease (such as TM Ultra or Montana X-Treme) to your bolt lugs after every cleaning to help to prevent bolt lug galling.
Never fire your rifle without first running a dry patch down your bore to insure you have no bore obstructions, or excessive oil in your barrel.
I always fire two "fouling shots" before I hunt with a recently cleaned barrel – or rely on a shot for sighting in. You will note that the point of impact may be off as much as ½ inch at 100 yards within the first two shots.
Persistent Carbon Fouling
At about every 300-500 rounds fired, we recommend cleaning out any carbon build up in your bore. This can be seen with a bore scope, if available. Or this may be needed if you have an unexplained degradation of accuracy. Carbon typically builds up in the first 1-12 inches of your bore. So this is the area that must be cleaned.
First, clean your barrel with the above outlined procedure for a general bore cleaning, to remove copper fouling. Now we can begin to remove the carbon build up. Iosso Bore Paste may be the most effective way available to remove carbon build up. Iosso Bore Paste is a mild abrasive paste. Coat a patch with a layer of paste, and using a jag and bore guide, push the jag into the first 6 inches of bore, from the chamber end, and stroke the area 3-4 times back and forth. Then stroke out to 12 inches 2-3 times, working back and forth from chamber to 12 inches out.
Lastly, push the patch all the way out the barrel with no back and forth strokes past the 12 inch mark. The patch will be black. This is a reaction with the paste and barrel steel. Don't assume you need to repeat this procedure. Doing it just once has proven to remove 90% of carbon fouling. Now using bore cleaner and jagged patches, push a multitude of patches wet and dry through the bore to remove any and all remaining paste, and once again swab out the chamber.
Over-use of any abrasive in a custom barrel will damage the bore, so follow these instructions carefully and do not overuse.
Firing pin and internal bolt cleaning is best accomplished by a certified gunsmith, special tools may be required for the removal of the firing pin assembly from the bolt. All Long Range Rifles are properly lubed at the shop. If you experience problems with your rifle's bolt and firing pin assembly or have exposed your rifles bolt to excessive dirt, grit or water, have your bolt internals cleaned and lubricated immediately.
Trigger cleaning is normally accomplished by removing the barreled action and spraying lighter fluid or alcohol into the mechanism and then blowing dry with compressed air. Using oil in a trigger can cause a buildup of dust and sludge leading to a possible malfunction. Keep your triggers clean and dry for best results.
Muzzle Brake Cleaning
Carbon build up in a muzzle brake can cause a degradation of accuracy when the buildup gets heavy. Clean your brakes at regular intervals. If you feel a muzzle accessory is causing an accuracy issue, remove it and test fire your gun to eliminate it as a possible source. Soaking and brushing seem to be the preferred method of brake cleaning.
Be careful not to damage your rifle's crown when cleaning muzzle accessories.
Long Range Rifles, LLC
***********************************
.