I don't understand copper fouling

Any copper solvent would be fine. Hoppe's #9 I use to neutralize the other solvents, #9 will not harm the barrel but may not be strong enough to remove heavy copper fouling. When shooting high powered copper rounds you want a cleaner to remove carbon & copper.Check out MidwayUSA there are many solvents to pick from, Now my choice is KG-1 & KG-12 Follow the instructions on the solvent, let the solvent do the work, use a bore guide & a one piece rod, wipe the rod with each pass down the barrel, make sure your patch isn't to tight, you don't want to bow your rod as it's going down the bore.Hope I helped.
 
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I think any lapping a bore is a waste of time unless you have a precision hole gauge to measure what you're doing. Otherwise, all you're doing is making the bore and groove diameters unevenly larger.

A little copper fouling in a rough bore makes them shoot more accurate. Very little bullet jacket is rubbed off and good accuracy happens.
 
It's all about "soft metals," like lead, copper, gold, brass and...mercury. When the force of the gas expansion pushes a bullet through a controlled bore, the compensator to make it spin is the rifling. Crud does accumulate in the rifling as the soft metal of the bullet does its work. It's no different than a sewer line that collects what has to diminish. Cleaners all have different compounds to clean, and you need chemical with your brushes. Watch out for your gold inlays! Read the labels. Copper is harder than the mentioned above, and prevents the lead from leaving residue. I shoot only copper clad bullets through my barrels!

I use Ballistol to remove soft metals from my bore. Just don't use it on gold inlays!
 
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What does anyone think of fire lapping new rifle barrels that have not been hand lapped?
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I'm not a fan personally, but David Tubb seems to be sold on the process based on comments from his book. I'll have to admit that he knows a thing or two about rifle barrels and accuracy...
 
Having known David Tubb since the 1960's and shot many a match with him, he's also a marketing wizard. He knows how to make a buck off innocent people. Nobody else shooting top scores like him and knows as much as he does about barrels and accuracy fire laps.
 
David Tubb also uses Schneider barrels, which Bart B. notes don't last as long as equally accurate Hart or Krieger barrels. It is clear that David Tubb has a system that works well for him.

Fire lapping can make a barrel better, but it can also make a barrel worse. Either way it is not something that I recommend be done to a brand new barrel, factory or aftermarket.

Jimro
 
If the barrel is hammer forged does that negate the advantage of breaking in a barrel or firelapping?
 
No, how a barrel's made doesn't negate anything.

I think there really is no advantage of anything by breaking in or fire lapping a barrel except maybe an emotional one.
 
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Cut rifled, button rifled, hammer forged, broach cut, or even chemical etching all produce usable barrels.

No matter the barrel, it will generally get a little better as it it used, until it starts wearing out then it gets worse. No break in or fire lapping system is going to change that.

Firelapping may help a barrel getting towards the end of accurate life by cleaning up the throat a little, but at that point all you are well beyond any "break in" period.

Jimro
 
No matter the barrel, it will generally get a little better as it it used
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A popular misconception.

I think it was Black Hills that did a test with a rifle shooting their .308 Win. match ammo with 5-shot groups over a few thousand rounds. The barrel started out with sub 1/4" groups at 100 yards, then slowly opened up to 1/2" or more over about 4000 rounds. Average group size increased about 1/100th inch every few dozen shots.

Sierra Bullets' .308 Win test barrels are fired with 10-shot groups testing their 30 caliber match bullets 180 grains and lower. Starting out at sub 1/2" groups in their indoor range with reference bullets called "standards", every few dozen 10-shot test groups of production runs, they'll shoot one group with standards. The average with standards slowly gets bigger and at about 3000 rounds of barrel use, the standards would shoot about 3/4" groups; 3/8 MOA. That's their limit for test barrel accuracy.

Competitive shooters also notice their barrels getting less accurate over time then replace them when some limit's reached.

When one realizes that the bore starts eroding and wearing out starting with the first shot fired, it makes sense that there is a limit when accuracy is no longer suitable for its intended use.

Some years ago, military .30-06 barrels were subjected to accuracy tests over many thousands of rounds. Many barrels started out shooting about 5 MOA (30 inches) at 600 yards (specs were 7.5" mean radius at 600, does that for extreme spread) and after a couple thousand rounds, they improved a bit to shoot about 3 to 4 MOA. They would stay at about that size for a while, then worsen. At around 10,000 rounds, accuracy had dropped off past specs. Standard service ammo was used.
 
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Bart B.,

I like how you say it is a misconception, give an example that supports your point, then contradict yourself with a data point that supports the "common misconception" :rolleyes:

There is an exception to every rule, including this one.

Jimro
 
Jimro, I put both points in print to show both schools of thought. One for super accurate stuff and the other for improved cylinder bore patterning. I hoped someone would note the contradictdion.

Thanks for being the first to mention it. The second one about military barrels was put in one of Sierra Bullets early reloading manuals about barrel life and I've seen it in different forms elsewhere. I think it was done to calibrate the throat erosion gauge used to indicate barrel wear and when the barrel should be replaced. Barrels were typically replaced when it went in alll the way and read "10" at about 10,000 rounds of life. I do know that that .30-06 throat erosion gauge was used on military .30-06 M1 and 7.62 NATO M14 and M1 match conditioned rifles; when it read "5" at around 5000 rounds, the barrel was no longer good enough for the old military A, B and C targets used until around 1970. Arsenal match ammo spec was 3.5" mean radius at 600 yards; about 15" or 2.5 MOA extreme spread.
 
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There is certainly an advantage to a properly lapped barrel. A properly lapped barrel will tend to copper foul less and therefore will shoot more accurately over a long shooting session than one that copper fouls rapidly.

In addition, if a barrel-maker makes the original barrel knowing that it will be lapped before delivery, he can compensate for the "wear" that lapping will put on the barrel by starting the barrel out with slightly (VERY slightly) smaller dimensions. That's a little different than taking a factory bore and lapping it.
 
Also hand lapping can leave a slight contour in the bore which gives an easier transition into the rifling.

Jimro
 
Real match grade barrels are lapped with a brass or lead lap sized to the bore/groove diameters then charged with a fine lapping compound. It's run back and forth in the bore and the bore's measured with an air gauge or precision deep hole micrometer. The lap is cleaned and recharged a few times in the process as well as the bore being cleaned.

The objective is to remove all the rifling tool marks (that otherwise would easily get copper fouling) and get a uniform groove diameter spread to less than .0001" for the length of the bore except for the first inch at each end that's slightly belled from the rifling tool. The muzzle end's marked where its bell starts and the breech end gets cleaned up by the chamber reamer. A microinch finish of about 12 to 16 is smooth enough to minimize copper fouling. Any smoother and copper fouling tends to get worse. It can take an hour's labor to do it right.

Any smoothing, lapping, conditioning of the origin of the rifling at the leade is soon eroded away by high pressure/temperature gases from burning powder. It starts getting rough with the first round fired.
 
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A copper clad or guilding metal jacketed, when fired, the softer heavier metal, copper, is literally liquified, by the heat ,pressure and friction of the forces involved in the process. It doesn't puddle,it's smeared, I guess might describe it sorta, the length of the barrel. This in essence laps the barrel, making subsequent shots subject to less friction.

I have been reloading for magnum and high powered rifles since 1975. I have observed the fouling shot in numerous rifles. Some barrels foul differently than some others. I have probably spent more time removing it than applying it.

Magnum rifles foul quicker I believe. At least my 300WBY Vanguard fouls pretty quick with warm handloads. The hotter you get your barrel the quicker it will foul. I sometimes shoot quick and cool the barrel every 3 shots with rubbing alcohol, on a rag to the outside, and with a patch on a mop to the inside. This seems to slow it down some and I think the isoprpyl washes a little of the carbon out. Carbon is gritty where copper is smooth, but lead fouling is lumpy, being removed.

As far as removal goes almost all methods suggested will work. I use Barnes CR10. I am reluctant to use abrasives on anything but the roughest bore. I tried it once on 300WBY because I kept getting so much blue for so long. Then I started trying the alcohol thing and it no longer seems to take as long to get better patches.

Anyway, copper removal is payback for our loving to shoot as much as we do. Just gotta get used to it. The same patience goes in to reloading also.
 
Putting copper fouling in perspective. . . . .

Bullet copper jackets melt at about 2200 deg F. I don't think they melt when shot. Copper fouling happens when jacket material is scraped off by the sandpaper finish of the bore.

If more copper fouling makes less friction between subsequent bullet and barrel, that means subsequent shots will have lower muzzle velocity. In the few velocity tests I've run, the first few shots starting out from a squeaky clean bore increase in velocity by a few fps, then stabilize and remain constant for dozens of shots. The smoother the bore, the less shots it takes for muzzle velocity to stabilize.

I've not noticed any difference in copper fouling between a .308 Win and 30 caliber magnums. Nor when fired 20 to 30 shots 10 times a minute or once every 10 minutes.

I think the time taken to apply copper fouling a barrel is equal to the number of shots fired multiplied by barrel time. If it takes 5 shots to foul a barrel and barrel time is .0011 second, .0055 second is how much time it took to foul the barrel.
 
If jackets liquified so would the lead core. A puddle of molten metal at mach 2+ spinning at several thousand RPMs hits air it'll simply burst into a spray of atomized particles at the muzzle.

AS that doesn't happen I don't think melted metal is happening.
 
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