Breaking in my barrel.....

[Art Eatman]

He built the rifle(s) he used in benchrest competition, and for all I know still holds the record for smallest group ever shot.

http://www.shootingtimes.com/2010/09/23/longgun_reviews_st_legacyofps_200911/

0.000" is somewhat above average.

 

[denton]

Based on a bit of experience, and even more conjecture, I offer the following model, which I follow:

Some barrels need break in. Some do not. Your barrel will tell you what it needs, if you will listen. Shoot one shot and clean with a copper remover. Shoot a second shot and clean with a copper remover. If you're getting a lot of copper on the patch, you need to do a break-in. If not, go shooting and have fun.

When the bore is absolutely clean, only the first shot through the barrel counts as break-in. The microburrs and irregularities scrape copper off the jacket, and each successive shot builds up more copper. Only when the microburrs and irregularities are "naked" does the bullet passage smooth them down.

I have a 1917 milsurp Swede which copper fouled excessively. After just under 100 years of being shot, it still was not properly broken-in. I cleaned it very thoroughly, shot one shot, cleaned again, repeating for about a dozen shots. Then I shot three shots and cleaned, and repeated that a few times. I may have expended 30 cartridges. At the end of the treatment, I was getting very little copper on the patch. The rifle now will go a long time between cleanings.

Gale McMillan's article throws down the challenge for someone to explain what is gained by break-in. The answer is very simple: It allows you to go longer between cleanings. If a rifle is properly made in the first place, or broken in properly if it requires that, you can shoot more shots before copper fouling impairs accuracy.

 

[Nickb45]

I just bought a new RRA Predator pursuit. I heard it was a real tack driver, so I wanted to get the most out of my barrel. I talked to a few local varmint shooters about break in. They told me pretty much the same thing Rock River told me, if the shooter has to break in a barrel then the barrel was never properly finished.

I ran a patch down my new bore and went shooting.
This is from 100 yards, out of an off the shelf, stock AR.

 

[Robert101]

I too have a very similar opinion as Denton describes. Break-in is very barrel dependent. I would also go as far to say that a properly lapped barrel is a form of break-in in its own right. So to that end, I do realize that fine target barrels have already been prepped so it should also be noted that more standard barrels will require attention to smooth the bore.

 

[taliv]

the barrel maker can't lap the throat/leade, which is the only area affected by a proper breakin

 

[W.E.G.]

If you are winning the high master class you already know how to manage your barrels.

If you are not winning the high master class, no amount of barrel break-in voodoo is going to improve your scores.

 

[Cesiumsponge]

I followed the near universal advice from Accuracy International and Sako TRG owners when I bought my TRG.

Shoot until accuracy is affected.. Clean. Note deviation between cold clean bore shot and fouled shot. Go back to step one.

I could clear 1/2" dot drills if I did my part and an actual skilled shooter (I am mediocre at best) could likely wring 3/8moa Hard to imagine lack of break-in affected overall inherent accuracy of the barrel. Then again, it's a lowly military precision bolt gun and not a benchrest machine.

 

[HexHead]

Well, according to Weatherby's recommendation, you've already done it wrong. While there's nothing in their owner's manuals about break in, there is on their website under the FAQ section.

They recommend using a 40 shot regiment. For the first 10, clean and allow the barrel to cool between each shot. For the next 30, clean and allow the barrel to cool between the ten 3-shot groups.

You might as well just shoot your rifle and enjoy it, the horse has already left the barn.

 

[Cervus canadensis]

Here is what Weatherby says:

http://www.weatherby.com/support/faq/item/view/44344

TWO BOX BARREL BREAK-IN
This barrel break-in procedure requires two boxes of ammunition to complete. Start out by shooting one round at a time, cleaning the barrel thoroughly after each round and allowing it to cool. This process should be followed for a total of ten rounds.

Then take the remaining thirty rounds and shoot ten three shot groups, cleaning the barrel thoroughly after each group and allowing it to cool completely before firing the next group. Once ten, three shot groups have been fired the barrel is adequately broken in. At this point the rifle can be sighted in and used.

---The above is from the Weatherby site.

 

[denton]

If you thoroughly, deeply clean your barrel so that all copper has been removed, you are back to square one and can do a break-in if your barrel needs it. Note the example of the nearly 100 year old Swedish Mauser.

 

[taliv]

once the tool marks are out of the throat, there's no further point in doing a break in. so if you've fired it a bunch and then removed ALL the copper, just go ahead and shoot. no point in doing break in

 

[USSR]

taliv is correct. Even with hand lapped custom barrels, the throat is the one area that requires attention thru the process called "barrel breakin". And the reason is as denton stated: "It allows you to go longer between cleanings. If a rifle is properly made in the first place, or broken in properly if it requires that, you can shoot more shots before copper fouling impairs accuracy".

Don