Barrel fouling question

AL45

New member
I have a .308 H&R Ultra Hunter which takes three fouling shots before it is on target. Then it will shoot 2 to 3 inch groups at 100 yards. I thought it might have to do with the barrel warming up, but I shot it several times, left it dirty, and shot it several days later and it was still on target. The first shot after cleaning is several inches high, the second is a couple of inches high, and each preceding shot groups well. Any thoughts?
 
Copper jackets, at centerfire rifle pressures will strip in the barrel. Meaning that friction at MV is melting copper into the grooves. This smooths and in essence laps the inconsistancies in the grooves, I believe that this reduces friction and makes subsequent shots more consistent and more accurate. Many rifles only require one fouling shot and then will group true to form.

Some use this argument to challenge the need for barrel break in. On my magnum rifles this principle is extreme. Too much copper builds up in the bore and accuracy diminishes, starting after about 20 rounds in a 300WBY. I spend more time removing copper than I do applying it.
 
It's common for factory and standard service rifle barrels to scrape jacket material off the first few bullets. After the micro pits and grooves are full of copper, no more's washed off and they shoot decent. Bullets with jacket material wiped off are unbalanced; they don't shoot accurate.

Top quality match barrels won't do that; they shoot to point of aim starting with the first shot and do so for hundreds of rounds thereafter.

Leave that copper in the barrel; it won't hurt anything. Just do simple cleaning and nobody will know about it and your rifle will shoot well thereafter.
 
I have a NEF/H&R in .223 that is about the same. Bore isn't the smoothest I've seen and it takes 3-5 shots for it to settle back to it's precleaning zero. Just a fact of life so I don't clean that rifle often.
 
Thanks for your responses. I posted this on another gun talk site and no one said anything about copper fouling. Most simply said, in some rifles you have to get the barrel "dirty" by shooting a couple of shots, before it will shoot accurately. Your copper explanation makes a lot more sense.
 
Each rifle barrel is an individual, and behaves slightly differently. However, there are some generalities that hold true.

Copper fouling smooths the barrel, to a point. Lead fouling is "lumpy".

A clean unfouled barrel usually shoots to a slightly different point of impact than a fouled barrel. Some rifles settle down after a single fouling shot, others take a few shots before they get consistant.

When fouling reaches a certain point, accuracy diminishes. So, for best accuracy, you need some, but not too much fouling. And what the right amount is, is different for every rifle.

I have known accuracy fanatics who clean bores completely after 20 rnds. Most of us only do it when accuracy starts to decrease. With .22s, it can take dozens, or sometimes even hundreds of rounds for a barrel to reach the point of max accuracy, but .22 rimfires are a bit different than centerfires in this regard.

I know hunters who will not clean the bores of their rifles at all during hunting season (unless they get dunked or something similar), simply because the cleaning will change that all important first round point of impact. They sight the gun in, and leave it (the bore) alone all season.

Another old timer trick is leaving the gun in the cold. Taking the gun into a warm cabin or tent at the end of the day means condensation (water) will form on the metal, and even inside the action. This is a bad thing, because it means the gun has to be taken down, wiped clean and oiled, or problems can result. And not just rust. Water in the mechanism will freeze when it goes back out in the cold, and causes trouble that way, as well.

What your .308 is doing is normal, if a bit on the upper end of the normal range. Now that you know, its easy to live with, just consider it a quirk of the gun.

We have a built in bias about cleaning our guns. This comes from the hundreds of years of shooting only black powder, where NOT cleaning the gun as soon as practical after use meant damage to the bore, and eventually the rest of the gun as well. And the military's phobia about a dirty weapon adds to it. Now, there are good, and sound reasons to clean everytime it is possible, but most situations ordinary folks have don't make it a necessity.

Enjoy your .308, and clean as you see fit. Maybe try differnt things and see what it does, and doesn't do. Once you know, its just a matter of doing (or not doing) what gives the best results for your use.
 
44AMP, the military's phobia about a dirty weapon was never based on accuracy with or without a copper fouled bore. 'Twas based on wanting weapon users to ensure their weapon was in good enough condition to shoot without a stoppage. There was more to keep clean and cared for than just the bore. Corrosion was the biggest concern.

Besides, a good centerfire sporting barrel will shoot several hundred shots without cleaning before accuracy gets worse than 1 MOA. And military combat rifle barrels will shoot 2 to 3 MOA for a thousand or more rounds of military ammo without cleaning; that's typically their accuracy spec.
 
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Sorry if I gave the impression I thought the military's obsession with cleaning was due to their concerns about accuracy. I know its not. I just meant that military training about keeping weapons clean is part of our built in firearms heritage.

I spent a few years working for our Uncle Sam, as a Small Arms Repairman, and I'm pretty well aquainted with the Army's concerns about accuracy in general (and standards for overseas shipment),as well as a few other things.

You're entirely right, concerns about accuracy and bore fouling are not the reason you clean your weapons every chance you get.

Got any idea the Army accuracy standard for overseas shipment for the M16A1 in the 1970s?

8 MOA

That's right, 8 MOA! IF a rifle wouldn't meet this standard, it was retained in the states for training use.

I was personally involved with several thousand M16A1s that were sent overseas. Got any idea how many were tested to ensure that they met the 8MOA standard?

0

Zero


With those guns, at that time, function was important. Accuracy wasn't.

I'm guessing, of course, but while I know many details have changed in the last 40 years, I doubt everything has...
 
I like to keep my rifles clean to a point, (basic training) the bore fouling is the biggest problem I have, and now it's only minor. See copperfouling can build enough to impede accuracy, and what I learned was that until it diminished accuracy, there was no need to worry about it. But once accuracy left and copper fouling was the culprit then I started using a product called Eliminator from Bore Tech, and it works, I tested about five of the newest copper removers and this one won hands down.
Anyway if the accuracy hasn't suffered then don't work yourself to the bone, but when it does get the best copper fouling remover.;)
And AMP, Bart, a big part of cleaning rifles in the military was Discipline, and being able to do exactly as told.:)
 
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^^
I agree with .243win. If you're getting 3 inch groups at 100yrds there's something wrong. My M77 in .270win will put bullets on top of each other at that range, and Rugers aren't exactly known for their stellar accuracy.

I should note that I am anal about keeping the bore clean, I follow barrel break-in procedures. And my rifle does not need any "fouling shots" for it to shoot at it's best.
 
It has shot 1 inch groups when I did my part by holding it steady over a sandbag. Most groups are slightly larger, but might be the shooters fault. The deer my son killed never asked what size a group the gun shot.LOL
 
Chuck Hawks is dead wrong. With a 1/2" MOA rifle I have a 1 " group at 200. If I make a 3 MOA mistake I now have missed by no less than 5 nor no more than 7 Inches. I hit vitals in the whitetail if only barely. If I have a 3 MOA rifle and I miss by 3 MOA, I might have a dead hit. I might also be 12" away from point of aim and flat miss the animal or the kill zone. If Chuck is right, we all need to get very inacurate rifles and hope the bullet strays toward what we intended to aim at.
 
Good point Reynold

I certainly don't advocate ignoring accuracy of a hunting rifle. And Hawks suggesting that 3 MOA is adequate is contrary to my personal standards. He has his own opinion.
 
Quote: He goes on to say that a rifle that shoots 1 inch groups isn't a bit deadlier than a rifle that shoots 3 inch groups at a hundred yards.
This sounds ridiculous to me, I must have (ocd's) sub moa accuracy from my rifle and my ammo before it goes afield, this is to make up for the 3 moa shooter that I am!!;) From a standing position (unsupported) like many cases during the hunting season, it takes evry bit of accuracy I can ring out of my rifle, cause you never know what position you will find yourself in, and frankly I love the very notion that my rifles shoot less than 3/4 moa from the bench!:)

I use Bore Tech Eliminator for my copper fouling issues, it works.;)
 
A 2-3" group is unacceptable. But you are cleaning your barrrel too often. It is normal for a barrel to shoot much more accuately after being fouled. I clean mine only after 200-300 rounds, or if accuarcy starts to drop off. After a cleaning I won't hunt with any of mine until 10-12 more shots have been down the tube. It takes about that many for optimum accuracy to return.
 
Some rifles need fouling shots to shoot to point of aim.
I have three rifles out of 8 that don't shoot the first rounds to point of aim after cleaning.
One takes 2 shots to stablize, the other two take 3 or 4.
The points of impact are high on one and low right on the other two.

My other rifles basically are pretty much at point of aim from the first shot.
Once the barrels are fouled, they are predictable and group well.

Accuracy for a hunting rifle:
I don't have any modern rifles that don't group under 1 MOA. One or two are just under. My .308 is a solid 1/2 MOA rifle with its 25 favorite hand loads.

Service rifles are a different matter as the posters have indicated.
I would agree that 2-3 inch groups at 100 yards with a hunting rifle would unacceptable if you are shooting off a rest or prone, especially with a .308.

If you are standing unsupported it would be different. Then it is probably the shooter more than the rifle that is causing the groups to open up.
 
For practical puposes, Hawks is correct (unless you're shooting from a machine rest:

The accuracy at target is the root-mean square value of the combined rifle precision and the shooter's hold.
Unless tricked up with sandbags, normal hunting conditions will greatly overshadow all but the most inaccurate rifles:

to wit if you're really good with target hold in hunting conditions at 100 yards:

0.5" rifle/3" target hold => 3.04" CEP at the target
1.5" rifle/3" target hold => 3.35" CEP at the target
3.0" rifle/3" target hold => 4.24" CEP at the target

... little practical difference for anything but headshots at ground squirrels...
(which is not to say that I always want the more accurate rifle anyway)
 
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