Copper Removal Technique: Break-in vs Complete Removal

[bill123]

When shooting precision begins to deteriorate in the past, I've "completely" removed the copper fouling and started the break in process as if the barrel were new. Depending on who you ask, the break-in process is something like: shoot 1 then clean, shoot 2 then clean, etc. until very little copper comes off on the patches. Then it's considered broken in.

My question is, how does the cleaning procedure for "complete" removal differ from break-in removal? It seems to me that if you used the "complete removal" procedure during each step of the break-in, you would remove all of the copper at each cleaning and essentially end up with a barrel that wasn't broken in.

 

[azsugarbear]

To my mind, there is only one "break in" period - and that is when the barrel is brand new. Custom barrels that come lapped from the manufacturer generally require less "break in" than production rifle barrels.

There are also several schools of thought on how you break in a barrel and how often you should clean it thereafter. Additionally, when discussing the process of cleaning and break in, we need to be specific as to what is being removed: the copper, the carbon fouling - or both.

Most custom barrel manufacturers seem to advocate a break in process that seems to be favored by the benchrest crowd. Shoot one, then remove both carbon and copper. Repeat 2-3 more times. Then shoot 3 bullets and then remove both carbon and copper. Repeat 2-3 more times. And finally, shoot 5 bullets and clean both carbon and copper. Once you see that very little copper is being removed by your cleaning - your barrel is broken in. Thereafter, clean out both carbon and copper after every 50 to 100 rounds. There's lots of room for variations in what is described above.

Another school of thought is to leave the copper in the new barrel, as it helps protect it from future erosion. This break in process is similar to that above, except you only clean out the carbon fouling after each round, letting the copper build up. Then you shoot your 3 bullet series, but only clean out the carbon. Then just shoot without cleaning until your barrel builds up enough carbon that it hits "equilibrium" (when velocity seems climb and then finally plateau). You then shoot hundreds of rounds without cleaning again until velocity begins to spike. Then you only clean out all the carbon (leaving the original copper) and once again start building up that initial carbon base until your barrel gets back to equilibrium. See the Sniper 101 series on youtube.com for a clearer picture of this method).

There are a few other cleaning regimens I know of, but the two described above seem to best illustrate the extreme positions that shooters can have on the topic of barrel break in and cleaning.

 

[notajeep]

In March I ordered a match barrel, still don't have it. So I've been reading a whole lot about this barrel break in thing. Pretty much unless your shooting with a 50X scope at 1000 yard targets don't do anything out of the ordinary. Clean it first before you shoot it.

Here's a great example I read earlier somewhere. .300 win mag barrel life (SHORT). So if you spend 500 rounds of breaking in the barrel and hunting for the perfect load data. What you have just done is wasted a large percentage of that barrels life. Again just something I read on the internet, but sounded logical to me.

As for all this coper solvent, with my .308 If I clean 100% of the copper out of the barrel my groups open up for the first half dozen shots. Go figure! I pretty much don't do copper solvent unless I'm putting something in long term storage or maybe if I was going to sell it. I've also read some barrel mfg's don't want it sitting for any length of time in their quality barrels.

Good Luck

 

[Greyfox]

In my experience the effect of break in is different, depending on the barrel. For the custom and high quality factory rifle like the Cooper, break in using shoot 1 clean for 10 shots, shoot 5, clean, etc. seems to take care of it in under 25 shots. Sometimes much less or not at all. For some factory barrels, it's much more, and cleaning is always a chore, even after break in. The indication for me on a broken in barrel is the ease copper and carbon removal which is noticeably different between the first shots taken, and the final result. Also, velocities/ES stabilize. Even with customs that are well broken in, it is rare to not see some copper removed when cleaning. Some believe this is just copper vapor residue. Having owned four rifles with R5 barrels, it seems that they break in fast, clean easy, and will shoot very large numbers of rounds without cleaning with no effect on accuracy. I believe this is why they are preferred by the military. I use them on my tactical/competition rifles where shooting volume is high. Also, just finished a 300WM LR hunting rifle that has an R5 barrel. It took less than 15 rounds to break it in. After loadwork, I have only shot 50 rounds without cleaning but accuracy and velocity were maintained. Cleaning was complete with a few runs of Boretech. It then takes 4 shots to re-establish the prior velocity, ES, and accuracy. This is what I look for in a broken in barrel on a hunting rifle.

 

[Grumulkin]

The purpose of barrel break in is to smooth out minor irregularities in the bore. It only needs to be done once.

Whether or not a barrel needs t be fouled to shoot its best depends on the barrel; some need to be fouled and some don't.

When I clean barrels to bare steel, I use Wipe Out and Wipe Out Accelerator to remove copper. I've left Wipe Out in barrels for days with never any indication of rust; I wouldn't do this with some other products. For a new barrel, I clean it before shooting and then every 10 to 20 shots for the first 100 rounds removing ALL copper. I then apply Microlon Gun Juice. Barrels I've treated with Microlon Gun Juice seem to foul much less easily than barrels that haven't been so treated and I believe it ******* barrel wear.

For a quick clean to remove carbon/powder residue, I use Prolix. You could also use Microlon Gun Juice but it's more expensive. I never put or leave gun oil in a barrel.

 

[Mikecr]

I've yet to see copper fouling as good for accuracy. But then, I don't load develop with a bunch of copper in my barrel. For me, I can clearly see when I'm copper fouled-out, as shooting results take a step change.

My initial break-in, to knock out high spots/constrictions in the bore responsible for collecting/building early copper, is 10shts of Tubb's FinalFinish. Then I don't ever let copper collect in bores, as I fully clean them after every use. This, even though I could technically go hundreds of rounds before copper fouling-out, because my bullets are all tungsten coated.
I just don't like copper building at all.

Even more of a concern to me is carbon buildup. Copper is an annoyance, but carbon is THE barrel killer. By the time you're trying to figure how how to refurbish a bore, that has taken a step change in performance and showing more copper buildup(where OP seems to be), you got a tough problem on your hands. 'Fixing' this can forever kill your bore.
For analogy consider the common end of a bore that was subjected to moly coated shooting. The moly builds up a bit down the bore, constricting the bore there eventually to hurt accuracy. Now removal of that moly constriction involves abrasive work(a lot of work) that is as likely to ruin the bore. It's less effort to replace that barrel..
Carbon is very similar. It impinges into the surface of the bore, and building on top of itself, eventually constricting the bore. Like moly it cannot be chemically removed. Normal cleaning only wipes away the loose carbon leaving the evil bad stuff. This has to be abraded away with routine/light use of something like IOSSO cleaner or J-B bore cleaner(not polishes, don't ever use polish).
You gotta look to the future & stay on top of it.

Problem carbon is impinged where the bore surface is hottest, in/near the throat for a few inches.
So a barrel that anyone would agree as 'shot out' & again leaving copper, can be reborn by setback(moving chamber forward). But if you had to do this there is still carbon impinged forward of the new chamber, and your reborn barrel will not shoot well as long as it did originally. Time for another setback, or barrel replacement.
This is not re-breaking-in a barrel. I can't imagine how a bore would need further breaking in after initial. I do however dress up lands every few hundred rounds with a shooting of a few Tubb's TMS bullets.

Before pitching a barrel, and given that you've got nothing to lose, try Tubb's FF. You never know, it might work, and the firelapping finish it leaves is apparently similar to the lapped finish in the best aftermarket barrels. I say this because it has not hurt/affected fouling from my aftermarket barrels(which clean up super easy).

I've pretty much decided to try melonite treating of future barrels. I think this will change barrel life and cleaning for it.

 

[Pdvdh]

I've yet to see copper fouling as good for accuracy.

I've pretty much decided to try melonite treating of future barrels. I think this will change barrel life and cleaning for it.

Interesting read Mike. Thanks for posting. I've got a new barrel in for melonite treatment now, and my future aftermarket barrels will also be melonite treated - based on what I've researched to date. Excellent corrosion resistance and increased bore life are the two selling points for me.

The only drawback: no further machine work is possible since the surface is so hardened that it will dull chamber reamers and machining tools.

 

[bill123]

Thanks everyone for the great replies. I learned a great deal!