I have read many posts on the different methods used by folks to break in their barrels , but one thing I have not seen addressed is WHY. What does this process actually do?

Smooths up and deburrs the bore, maybe?? I honestly don't know, as I have never done this! And, I have had a few rifles that shot pretty good right out of the box, too. But there are enough experts who recommend this procedure that there may just be something to it. Or it could be just like carving Pennsylvania Dutch hex signs on your long rifle stock, to keep the evil spirits at bay!!

I think this would be best explained if you visit some of the barrel makers web sites. If I remember correctly I think Lilja has an article on his web site on break-in. Dan's articles are worth checking out.

regards
Mike

I'm not sure it makes any noticable improvement. I did it with a new 300 WSM before the last hunting season. Here is the unique thing about breakin: You can do it easily enough. I mean, you are going to shoot anyway, so why not do it? It's just a sequence of shooting and cleaning. if it lives up to its billing, you are better off, is not, you got lots of practice cleaning.

I will say one thing about breaking in my 300 WSM. The rifle shoots three round into an inch out of a cold, clean barrel and does so every time. I will not say breaking in the barrel did this, but I can't say it didn't. I've had two other rifles that did the same, and several that threw the first round out of a cold, clean barrel out of the group and I didn't break them in. I plan to buy a new 270 WSM and will break it in. I'll see if it will shoot cold and clean into a small group. If it does, well, two experiments should quality as a new shooting religious otrhodoxy, shouldn't it?

[ 12-17-2002, 22:25: Message edited by: RogerK ]

Barrel break-in, I believe, is a process to keep the bore clean while regular shooting sort of "laps" the barrel smooth. While this is not specifically "fire lapping", it is accomplishing much the same thing of wearing down any microscopic burrs and machining marks on the bore. Cleaning regularly helps to keep the copper/lead/powder fouling from interfering with this process...or so I surmise.

On the other hand, many custom barrels already come hand lapped so the bore is already quite smooth. I suspect that break-in has much less impact on these barrels. Then I think...if you've already gone to the trouble of getting a custom barrel, why not do a little break-in?

Now for my own personal actions...I have only performed the break-in ritual with a couple barrels and don't really see any difference. So go figure!!

Your barrel will break itself in as you shoot it. The only reason most shooters do a formal break-in procedure is to get the barrel to show consistent performance quicker.

This all started with benchrest shooters who need to know if the new barrel on their rifle will be competitive or not....if not it gets replaced.

One other item to confuse you further....it isn't really the barrel itself you're breaking in, it the chamber throat as it's the only thing cut across the lines of the rifeling.

Having owned a number of new rifles and had a number of others re-barreled, I have tried it both ways. I broke them in doing it the way the bench rest people do it and then I have just taken the new rifle/barrel out and and zeroed the scope/sights with a box of 20, shot another box or two just for fun, cleaned it and that was it. I have not been able to see a difference in accuracy.

The theory behind barrel break in is that it smooths the microscopic holes and rough spots in the bore. While to the naked eye it could appear smooth, intensely magnified the bore would look like a well worn gravel road. Break in is a form of putting a road grader over it and smoothing it. 200 shots will do the same thing.

For the custom hand lapped barrels, some makers recommend break in and others say just go out and shoot. For the factory bores it would take probably 200 rounds or more to smooth the ridges in a cut barrel, maybe more, so it truly makes little sense to try to break one in. What it does help is to remove the copper from minor rough spots. Leaving it in builds the deposit more and more with each successive shot as copper from the bullet galls on the old deposit.

When I started shooting about 60 years ago, no one ever thought about break in. We bought guns and shot them. I agree that the benchresters with their hand lapped bores are probably the ones who started it all in the 60's and 70's as I never heard of it till then. I have some old rifles that are as accurate, or more so, with their factory barrels which weren't broken in, than some custom modern rifles that were meticulously broken in. I've never seen any difference. I've done it only because there are those that say it's necessary. In the last few custom rifles I've acquired what I have done is to run JB through the bore. About 500 passes changing patches every 20 passes or so. Then in the initial shots through it I've scoped the bore and cleaned out any copper in the first couple or three shots. When you can shoot a couple or three shots without leaving any copper, I've considered it broken in and have shot the gun as normal. The only tedious part of the whole thing is the J-B through the bore. Admittedly I've cheated and shot it after about 200 passes, but those guns treated in this manner are easy cleaners and don't accumulate copper. It has taken no more that 3 or 4 shots at the range before bullets go through without leaving copper deposits.

Bottom line is I think break in is unnecessary and over blown but I'm afraid not to do it as it can't hurt anything and for some reason there are those that say it's necessary.

Kreiger.com has a good page on that.

Chuck

Does anyone have links for the lilja or kreiger site's ? I would like to read those articles but cant find those pages. Also , what is J-B? Thanks

JB bore cleaner is a paste with very fine abrasives; it is used similar to a fine lapping compound to smooth out barrel imperfections - using a bore scope will reveal many "burrs" in a barrel - I do "break in" my barrels similar to PacNor recommendations; definetly allows easier cleaning if not better grouping - KMule

According to Lilja, and the local highpower competitors, it is designed to improve cleaning, not accuracy per se.

By cleaning after each shot, you remove the copper that collects in the microscopic valleys, so that subsequent shots wear down the microscopic hills. The whole idea is that by smoothing out the barrel, copper has less places to hide, so it is easier to clean.

It is definitely easier to clean. Just in the break-in process you can see it. During the first 15 or so shots it slowly gets easier to clean after each shot (or couple-5 shots starting after 15). By the time you reach 50, you can clean the barrel in half the time it took to clean it initially. I have seen it.

I don't think the advocates of break-in are really claiming better accuracy. They are claiming less fouling which means more consistency in pressure over a string of shots. Consistency is a good thing.

[QUOTE]Originally posted by TexasGunRunner:
[QB]
According to Lilja, and the local highpower competitors, it is designed to improve cleaning, not accuracy per se.

This tweaked my memory. I remembered something I didn't know I forgot. Or, I remembered something I didn't know I knew.

Cleaning did get easier as I broke in the barrel. Shooting the first round then cleaning took what seemed forever. That changed as I put more rounds through the barrel. When I finally stepped up to 3 round groups, it was taking 1/4 the time and patches to get a totally clean patch out of the bore. This is reason enough to do it.

PS: I used Barnes X bullets for the breakin.

So if the general idea is to smooth out the bore so as to not trap so much copper , then the bore paste idea that Kmule suggests should be a good one , correct? That would be basically hand lapping the barrel , would'nt it? If it makes any difference the barrel in question is on a .223 Ruger varmit/target rifle.

The primary purpose of barrel breakin is a barrel that cleans much easier. I practice barrel breakin on all my new barrels, and firmly believe it eliminates flyers. It is a form of lapping and is not going to harm the bore. I am not a fan of those aggresive abbrasive pastes. It is far better to smooth the bore out by breakin and firing some rounds through the bore. Aggresive bore paste and fire lapping are often overdone and shorten bore life considerably. If the bore is that rough and needs that much attention it is a bad bore from the start, and will never be a good shooter.

There are barrel makers that if you use a abbrasive paste it will void the warranty . The paste will round off the sharp edge of the rifleing .