Barrel break in

While interesting, the argument fails to deal with why fouling occurs in the first place. According to Krieger, the chambering is cut across the lay of the barrel steel, and results in extremely small file like ridges. These ridges strip away small amounts of bullet material, which is subsequently suspended in the powder gases, and then deposited along the barrel surface as the gas moves down the barrel.

Copper is much softer than barrel steel, so the comparison to an engine does not really hold up, as the piston rings are as hard as the cylinder walls. Firing a bullet without lubrication will remove these ridges in short order, and proper cleaning procedures are, despite what is written, benign. When I clean my barrels no brush is used, a bore guide keeps the jag centered, and when I use an ammonia based cleaner, it does not sit in the bore long enough to evaporate and cause damage. Consider that a barrel might be cleaned hundreds if not thousands of times throughout it's life, and when done properly, the accuracy of the barrel is not diminished except by throat erosion caused by propellant gases.

I agree that a burnished barrel is a good idea, and for the last few years I have treated mine with Microlon.
 
Thanks for all the great responses, this forum rocks!! There was a commnet about lapping the barrel earlier in the thread. I am thinking this is the way to go before even firing the rifles. Can any one reccomend a product and technique for doing this?
 
JB has 2 products, I am not sure which one is the coarser of the two, or if they are coarse enough to lap a barrel, but one is called Bore Brite and the other is called Bore cleaning compound.

There are also dedicated lapping compounds (check auto supply stores?) as well as Fire Lapping kits. I BELIEVE the premise of the fire lapping is that you have the lapping compound in the barrel and you fire the supplied lead bullets through the barrel to do the lapping. Someone can correct me if I am wrong there. If I could remember wher I saw the kits I could read up a bit more on it.
 
I admit that I am in the "shoot, clean, take another shot, clean, etc. etc. etc." camp;

However, I must ask myself, if this so called "break in" process is so important to the future performance of the barrel, then why do the major firearms manufacturers not recommend it so that their products perform well and hence get the reputation of shooting better than the others. I have yet to see even one sentence or any mention in the various "owners manuals" for new firearms that suggests a barrel "breaking in" process.

my $0.02

Gunsmoke
 
Folks reading through this thread make sure you keep things in context.
There are two categories... barrels that are lapped and those that aren't. Make you know know which one you have! It may seem pretty straight-forward but I have to wonder about someone who isn't one hundred percent sure decides they're going to lap a custom barrel that is already lapped... many customs are, there's a possibility that a few might not be...

running abrassive lapping compounds or the bullet kits through a brand new lapped barrel would seem counter productive. If you're trying to bring a barrel back that's a different story of course... generally once they're gone they're not coming back.... if they do it won't be for long...

I read through the instructions of a bullet lapping kit and the impression I got was hey if I use this on any new barrel it's got to shoot better or so the instructions say! Just be damn careful about why your doing this.

For example say someone had a custom barrel but for some reason it didn't shoot... they got a bullet kit, used it and then with a minimum of detail posted that they had fantastic results with using the kit. People might misunderstand what's going on and think they've gotta get themselves one of these kits and in doing so they think their barrel is going to shoot better period.

Even custom barrels can have a potential problem. For example during the lapping process something was missed, like a burr or the throat wasn't done as well as it could have been. I think this is highly unlikely but the possibility does exist. Also the odds of regular barrels benefitting would seem likely to be higher but not always...

watch what you are reading or make sure you're taking it in context. I'm surprised at the number of people who get caught by this...
 
Fire lapping may address reamer marks left by the chambering process in the leade and throat, even in a hand lapped barrel. It is not likely going to do much for the hand lapped actual bore. Hand lapping with a cast in place lap isn't going to deal with the leade.
As far as hand lapping goes, which custom barrel makers do not lap at all? Those who use button rifling often lap before the button is used. This is about the only way to eliminate reamer marks, and make sure the bore is free from loose or tight spots; the button doesn't eliminate reamer marks. Don't know if any button riflers lap after rifling. The process doesn't leave freshly cut edges. If a barrel is to be cut rifled, lapping is often done after rifling.
With respect to the engine analogy, piston rings are hard. Cylinder blocks or sleeves may be iron, which is softer than the rings.
 
This is a great thread, and I love the opinions being offered. It is giving me great cause for thought.

Barrel makers Ron Smith and McPhee do not lap their barrels. Both of them cut rifle and de-burr. Mick mcPhee is harshly critical of hand lapping and his opinion (I emphasize HIS) lapping is more about esthetics than performance. Mick DOES promote break-in. We agree to disagree, but then what does a great gunsmith like him care what a philistine like me thinks? :)

Because of the variable homogenicity of a single chunk of steel, and given that the "button" in button-rifled barrels - under 20,000 lbs force - pushes aside the material to create grooves (Cut rifling removes it) hand lapping is meant to help even out localized areas with more rigidity and elastic recoil that produce a very fine undulation down a barrel bore. When barrels are hand-lapped, there is the risk of over-lapping the middle and under lapping the chamber/muzzle ends, which can result in tighter muzzles than mid-barrel. Mick told me he has found a number of brand new button rifled barrels where he's had to cut off the ends to get a pilot to fit properly, from being short-lapped.

I personally look at the guys that are the best shooters in my club and at the matches i go to and I ask them what they do. They are split 50/50 on the break-in thing, and none of them lap.

It's been bashed many times on this board, but keep the comments coming!
 
jkajfes said:
running abrassive lapping compounds or the bullet kits through a brand new lapped barrel would seem counter productive. If you're trying to bring a barrel back that's a different story of course... generally once they're gone they're not coming back.... if they do it won't be for long...
Click to expand...

Actually the barrel I ran this kit through was a Rock 5R M24 barrel.And it DID improve its performance.I will definately repeat this on the next one I get.
 
Longshot said:
Actually the barrel I ran this kit through was a Rock 5R M24 barrel.And it DID improve its performance.I will definately repeat this on the next one I get.
Click to expand...

this is great when it works out no question about that... but the new one you are going to shoot it first before using a kit right?
 
Obtunded said:
It's been bashed many times on this board, but keep the comments coming!
Click to expand...

Ya no kidding, but it doesn't hurt to refresh it... The short stroking is something I keep forgetting about in conversations. Thanks for bringing that up... I would like to believe air gauging would possibly catch this or you could use that to discover something like this...

I would like to believe that most custom barrels are just that custom. You are paying for premium workmanship and I'm sure overall they are very careful in their procedures. I've had the complete procedure outlined to me on a number of occasions and the procedures vary. The biggest being cut vs button and moving on from there. How reamers are used, type of reamers and the benefits of them. All the reamers I have had made for me are the floating pilot types which seem to work extremely well.

A batch of steel though bang on in the spec department tolerance wise might be different than a previous batch and this may have potential to change the way a barrel groups. I've experienced that once.

There is no one solution that you can totally rely on as being definitive. Like anything there more than one route to take and generally you hope you arrive at the same distination.

I have read that a number of the BR shooters will buy several barrels shot them all and then pick the ones they will use for matches they consider important, possibly selling the rest. The ones they sell probably in most cases would be a level above some shooters capabilities so nothing is discovered... but a top competitor would see a difference. I also doubt they do much in the way of what we're talking about in this thread... break them in in otherwords... It might go something like this... 5 -10 rounds down the pipe and it goes in this pile or that pile.

Most of us are just trying to buy a single barrel we don't have this luxury. But if you could do that and the barrels you received came from two different batches with the same reamer being used for all of them or possible two different manufacturers and both were being chambered up at the same time that might be interesting to do. You might get a better appreciation for what's going on or rather notice the difference.

I've never used standard barrels. All of my rigs are custom built... bits and pieces from everywhere. I think the different break in procedures might work or you would see the most improvement on a factory barrel. I think customs are good to start with.

The last two barrels I had came from a completely new manufacturer to me. I mean I never had barrels from them before. The first day at the range I did a shoot clean for five shots and haven't done anything else. Same thing with the second one from the same manufacturer. Both are shooters they both group phenomenally well and let me tell you it's sure nice to have this happen!

I just won't buy a barrel made on a Monday... kidding of course I mean how do you know when it was made or tooled, right?
 
jkajfes said:
this is great when it works out no question about that... but the new one you are going to shoot it first before using a kit right?
Click to expand...

Yes I'll shoot a couple of groups through it first but I'm sure after that I'm going to want to run a kit through it.Not only did the kit make it group better,but it made cleaning way easier.When you push a patch through it there are no more tight spots.The patch goes through very evenly.Not to mention that it hardly fouls at all anymore.After the whole BC Sniper match there wasn't a speck of dirt in it.That,along with the better accuracy,is proof enough for me.I have another 5R barrel coming in 6mm and will use the same procedure on that one.
 
Boomer said:
While interesting, the argument fails to deal with why fouling occurs in the first place. According to Krieger, the chambering is cut across the lay of the barrel steel, and results in extremely small file like ridges. These ridges strip away small amounts of bullet material, which is subsequently suspended in the powder gases, and then deposited along the barrel surface as the gas moves down the barrel
Click to expand...

I believe this to be a good analogy as to what happens in a newly chambered barrel, regardless of the barrel's source. My new Long-range Krieger (6.5mm, 1-8" twist) laid a quite a bit of copper in the bore with the first shot fired. The bore was absolutely smooth and shiny before that shot. I cleaned and fired a second shot. More copper, but less that the first round. By round # 5, NO copper fouling whatsoever. I completed Krieger's recommended break-in, and it is a marvellously easy to clean tube. I am not convinced that break in has much to do with accuracy, except a heavily copper fouled bore will not deliver the accuracy that you will get from a bore that does not foul. The real benefit is easy cleanup in future after proper break-in. Some factory barrels are rough enough inside that regardless of break-in or cleaning methods, the accuracy degrades in a few shots (15-20) Good cleaning will bring accuracy back, but as soon as copper is deposited in any amount, cleaning will be required again. As with anything else, common sense should prevail....It should not take 100 rounds to break in a barrel. Regards, Eagleye.
 
barrel break in etc.

quote from Longshot

"I have used this on my .308 and it took it from .75 minute groups down to pretty regular .25 groups.Pehaps one of our sponsors carries it.If not they should.It works great."

I just mail ordered two of these kits from David Tubb's web site, for delivery to Vancouver. seems to have gone through payment fine, total with shipping was about $70 US (= about $76 Canadian today). so with our taxes and the add on $5 from Canada Post should be about $90 Canadian.

we'll see when it arrives, assuming no screw ups getting through customs, etc. they seem to know what they are doing as they accept Canadian addresses.

will let you know how it works out for my near new Rem 308 long ranger rig and my virgin 38 call PPC gun (will try a 'before and after' test for that one, after about 200 or so break in loads to see what accurracy is like before the treatment).

:rockOn:
 
My two cents: Custom barrels like Gaillard and Kreiger - lapped, air guaged, etc.

I do NOTHING to these barrels as there is no way I can maintain the supplied level of finish, tolerance and quality. The only thing I might do is a bit of POLISHING with JB bore brite in the throat/leade area to cut any rough spots. That will work out in firing anyways so no big deal.

If there is a problem with accuracy, I send the barrel back!

Are there differences in barrel performance? You better believe it. Barrels have a 'set' level of accuracy no matter what we do. The best we can hope is to extract what is already there. If you need a barrel shooting in the 1's and you get groups in the 3's with great ammo and proper rifle set up, nothing you do will make it shoot in the 1's. Time for another barrel. Expensive - Yes, but the only way to get a hummer or be competitive in some shooting sports.

Experienced target shooters will diagnose a barrel's potential within 25rds. Quality stuff either works or doesn't.

For factory barrels, I guage by how it shoots NOT by how it looks. I do not break in a barrel per the shoot one, clean process. Never found it to make a bit of difference. The best accuracy of ANY barrel is in the first 500rds. Why waste 100 of that making noise and potentially damaging the bore tolerances with improper cleaning?

I also never judge a barrel's performance by the colour of the cleaning patches. ALL factory barrels will have copper fouling to some degree. If you burn powder, it will make carbon soot. Bores get dirty so what? Holes in paper - that's what I want to see.

If a barrel falls off accuracy very quickly, 20shots, I will consider fouling as one possible problem area. I will polish with JB Bore brite especially in the throat area. This is done as little as possible as without the proper gear, I might do more harm then good.

In all the rifles I have own, I have had very few that needed to be cleaned after 15 to 25rds of fire. The vast majority of factory barrels didn't start shoot well until 10 to 15 rds were fired. The Savages I am presently shooting hang in there upwards of 75rds before needing a couple of patches.

The most consistent cold bore hunting rifle I had was a P17 Enfield with a bore rough enough to make a sidewalk feel like silk. Copper fouling was so bad, the bore was green! However, over 5yrs of use and very little cleaning, this rifle never hesitated to drop the first cold barrel shot into the target at any range from point blank to 850yds (sub MOA to boot). When I did clean it (rain or dirt), it needed upwards of 15rds of fouling to shoot well.

There are no trophies for bore appearance, just holes in target. If a barrel needs to be cleaned, I do so but only to the limit that gets the rifle shooting well. That is rarely ever to bare metal. NONE of my bores are spotless but they do shoot very well and very consistently.

Fire lapping does do a very good job of smoothing out the throat area but little for down the bore. Just remember that fire lapping is taking throat erosion and kicking it up a notch. Use with extreme caution as you may end up with a baby butt smooth throat and a 'shot out' barrel.

Jerry
 
Well said Jerry! but tell me... what sort of response have you had from sending a barrel back? Don't they tend to just blame the gunsmith?
 
I don't send back a barrel because it only shoots a smidge worse then expected. I am saying a BR barrel that is inconsistent enough to shoot 1/2 to 1 MOA. Barrel with visible rough spots or improper interior finish. Things that are tangible not because of poor shooting, rifle or load or 'just don't like it'.

Complaining that their match barrel will not shoot factory ammo or worse Surplus ammo sub MOA, will not get a positive response.

I have yet to see a barrel maker that guaranteed accuracy under the 2's (most don't guarantee anything at all), although many quality barrels will do so. For their reputation and pride, I feel that good suppliers will listen to you and if fair, they will respond.

You don't put the worlds best engine into a horrid chassis then complain that the car doesn't go fast. Give the engine/barrel a chance to do its thing and for the most part, owners will be thrilled.

My standards are a top quality BR barrel should AVERAGE in the 2's or smaller under proper conditions. A better aftermarket pipe, 3's to 1/2 MOA. Otherwise, I may as well just shoot the factory pipe and save my money.

Jerry
 
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