What Is A Clean Barrel?

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beltfed
Posts: 1962
Joined: Sun Jun 03, 2007 10:07 am
Location: Central Wi

Re: What Is A Clean Barrel?

Post by beltfed »

OH, After the alcohol patch, I run a dry patch thru before the Oily patch.
beltfed/arnie
Tuscarora
Posts: 26
Joined: Fri May 08, 2020 7:32 pm
Location: Utah

Re: What Is A Clean Barrel?

Post by Tuscarora »

Took what I am seeing just a bit further.

Shot thirty rounds of greasers two days ago, blow tubing between shots, and held accuracy to 300yds. Super!

Brought the gun home and first cleaned the barrel with Shiloh's bore cleaner. In that process a bronze bore brush was employed twice with 10 passes each time. A couple very small flecks of lead showed up on the first after brushing the first time. None after that. White patches began showing and I was done in maybe 10 minutes.

After dry patching the bore, MPro-7 was swabbed in the barrel and let sit for 15 minutes. Dirty patches! Brushing was employed again with no appearance of lead at all. I discontinued brushing, but letting the MPro-7 sit for 15 minutes at a time before wiping again. One hour later I had white patches again showing a clean barrel.

Then a patch of Hoppes was run through, and sure enough, in 5 minutes I had carbon on the patches. Another half hour to clean to white patches.

I am of the opinion that this is a hard carbon ring at the chamber. I believe my bras to not be too short and trimmed correctly, but the carbon shows up on the chamber end of the barrel.

So guys, the same question; what is a clean barrel in regards to a BPCR barrel? Is it when clean patches show up with a water based cleaner, or when the Hoppes has done it's job? I don't care for the thought of leaving carbon in the barrel to continue building possibly, or is it self limiting where it seems to be doing it? Though oiling after all cleaning, is this keeping me safe from pitting with a water based cleaner?
beltfed
Posts: 1962
Joined: Sun Jun 03, 2007 10:07 am
Location: Central Wi

Re: What Is A Clean Barrel?

Post by beltfed »

Tuscorora,
Again, After using a water based cleaner,
Wipe the bore with a patch wetted with 99% rubbing alcohol to remove any residual water
followed by a dry patch,
then oil patch
beltfed/arnie
Kurt
Posts: 8428
Joined: Wed Oct 12, 2005 10:28 pm
Location: Not Far enough NW in Illinois

Re: What Is A Clean Barrel?

Post by Kurt »

I used to use alcohol but I switched to the new WD-40 specialist. It displaces moisture and prevents flash rust. I also use it before I to the range to remove the oil.
But I don't think I would not use it for storage.
The reason a dog has so many friends is because he wags his tail instead of his tongue.

"Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery"Winston Churchill
charlie young
Posts: 1517
Joined: Sun Dec 05, 2004 7:44 pm
Location: froid, montana

Re: What Is A Clean Barrel?

Post by charlie young »

Just a thought, I don't know how many rounds thru your rifle. But when I was cleaning my last Shiloh I bought before I shot it, my patches got dirtier as I cleaned. I text Kirk wondering what was going on, he said don't panic, it's the bluing, don't know why it happened to this rifle, as it didn't to the previous three. Don't recall off hand exactly how many rounds and times I cleaned it until I was satisfied it was gone. I should go run a patch thru it again, after it's been sitting and see what it looks like.

Charlie
mdeland
Posts: 11708
Joined: Mon Nov 20, 2006 1:47 pm

Re: What Is A Clean Barrel?

Post by mdeland »

A barrel free of carbon fouling! It's beginning to appear to me that it creeps up on a shooter over time, is hard to detect and even harder to remove.
I think it may be the cause of previously accurate barrels going sour when no other apparent cause can be detected. I believe it is the reason a good lap job restores and often improves accuracy.
mdeland
Posts: 11708
Joined: Mon Nov 20, 2006 1:47 pm

Re: What Is A Clean Barrel?

Post by mdeland »

Another thought I had along these lines is carbon fouling may have been what the old chunk gun shooters used to refer to as "shooting smooth" ! The barrels were said to improve with barrel agitation when this occurred. Could it be the smooth was simply a layer of carbon fouling that accumulated over time lining a portion of the bore?
MSalyards
Posts: 270
Joined: Wed Feb 14, 2018 4:18 pm
Location: Nine Mile Falls Wa

Re: What Is A Clean Barrel?

Post by MSalyards »

I picked up a low wall a few years back that looked shot out smooth. After 2 weeks of scrubbing I found rifling's .
mdeland
Posts: 11708
Joined: Mon Nov 20, 2006 1:47 pm

Re: What Is A Clean Barrel?

Post by mdeland »

I'm currently in the middle of lapping a .270 barrel that went sour on me years ago in an attempt to get it shooting well again. I'll keep yall appraised of the success or failure of the venture. I need to stock it as well so it will be a while before it's all done and ready to go.
It's one of those back burner projects I'm finally getting around to fixing as the long dark, cold AK winter sets in again. :D
mdeland
Posts: 11708
Joined: Mon Nov 20, 2006 1:47 pm

Re: What Is A Clean Barrel?

Post by mdeland »

I managed to get the barrel level with a tiny bit of taper in the bore diameter of approximately .2715,so far . The . 271 gauge will go through smoothly with no impediments and .272 will barely inter the muzzle and will start quite a bit deeper in the breech end, this was with 220 grit . Tomorrow I will go to 400 grit and probably finish with 800. I count up and back with the lap as one trip.So far I've logged 750 trips with a lap refresh every 50.
Boy if a fella did this work with both arms he'd look like the Hulk inside of a year. :lol:
I find the smaller the caliber the harder they are to lap as the rods get more thin and bend easier. I'm thinking I may have to develop a push bull system for calibers in the 6MM on down diameters and perhaps shorter lap slugs.
beltfed
Posts: 1962
Joined: Sun Jun 03, 2007 10:07 am
Location: Central Wi

Re: What Is A Clean Barrel?

Post by beltfed »

Mike, that is a lot of work lapping. I am sure some barrels need that, BUT:

I expect that many barrels- all they would need is a 100 pull-throughs with a Bore Snake and
Turtle Wax Chrome Polish.
I just did it with a new Armalite AR 223 barrel. My Teslong Bore Scope inspection
shows it to be highly polished, Slick, Smooth and shiny.
First rounds out of the barrel with 55 gr Ball and 62 gr BTHP loads, resulted in Sub Minute groups
beltfed/arnie
Tuscarora
Posts: 26
Joined: Fri May 08, 2020 7:32 pm
Location: Utah

Re: What Is A Clean Barrel?

Post by Tuscarora »

mdeland,

Just curious to ask, what do you feel is an accurate round count on that 270? Most 270's coming from a hunting background, without bore damage such as rust, should last upwards of 2500-3500 rounds, or more.

In the Precision Rifle Series game, 80-100 rounds per match usually, shot fast and hot in 10 round relays under two minutes of time, tends to burn the 6mm's and 6.5mm's as fast or faster than the round count stated above. And what is usually seen is a loss of velocity from throat erosion, not a lack of accuracy per se. I have two rifles built for the grandkids, made from "shot out" barrels, with the chamber ends cut off, rethreaded and chambered, and are just as accurate as in their previous life. Just a tad slower with their shorter barrel lengths.

Tubb bore maintenance system bullets will accomplish what you're trying to do without the arm development.
mdeland
Posts: 11708
Joined: Mon Nov 20, 2006 1:47 pm

Re: What Is A Clean Barrel?

Post by mdeland »

The problem I have with any abrasive lapping Arnie, that is not applied with a rigid form fit slug, is that it wears off the high spots faster than the rest of the bore because of uneven form, expansive pressure. I speak of rounding land corners predominately which receive more cutting pressure than the rest of the bore and have the least area to resist it. With poured lap slugs the land corners keep their profiles which is not the case with a malleable lap. Once the high spots are gone the lead lap stops cutting that area of the bore.
The other advantage of a rigid lap is you can shape a bore to level, continual taper or choke taper at the muzzle.
Lapping is one of those deals that one keeps learning new things all the time and with bore scopes and plug gauges you can see and measure what is actually occurring.
I've been lapping now for over 30 years and have used fire lapping as well which is alright for pistol barrels but doesn't cut much past mid bore in a rifle length barrel. It also rounds off land corners in the throat area much faster than farther up bore. You simply do not have near the control over taper and profile that you do with a hand lap slug.
beltfed
Posts: 1962
Joined: Sun Jun 03, 2007 10:07 am
Location: Central Wi

Re: What Is A Clean Barrel?

Post by beltfed »

Mike,
The Turtle wax Chrome cleaner grit,etc is such that it will Polish the lands and grooves, but not wear off corners.
It is not a lapping compound. But a Polish.
It might even be a finishing touch after your lapping.
I just shot that 223 today again and at 100yds, I am sub minute on the cheap loads I shot. Next, I will try it with
some of my match loads.
Arnie
mdeland
Posts: 11708
Joined: Mon Nov 20, 2006 1:47 pm

Re: What Is A Clean Barrel?

Post by mdeland »

Tuscarora, I have never shot a barrel enough with jacket bullets to see a decline in accuracy from throat wear so don't actually know from experience when they start to go south. I shoot many thousands of lead bullets in regular competition and have also never seen one shot out.
What I have noticed though is accuracy decline from crown wear from a cleaning rod and I'm anal about cleaning. The best defense I've found against inside crown wear is a double slotted cleaning jag.
What happens is the rod clears the bore with a patch and then the bare rod rubs on the crown inside land tops with the fouling debris coating it behind the patch. Viewing the crown from the outside all looks pristine but if one takes a magnifier or bore scope and views from inside the bore at the lands end you will often note the land top will be unevenly shiny which is rod peening/wear. I experimented with both a 30-06 and .338 ( after a decade of use and noticing a slight decline in previous accuracy) by cutting back the crown to sharp rifling. In both cases they went back to the previous minute five shot accuracy.
I agree that cutting off and re-threading a barrel is good practice as a bore does not wear much from bullet friction. What wears them is the erosive heat and pressure in the throat and about 3-4 inches up bore. What happens is the heat and pressure begins cracking of the bore surface interior allowing the heat and pressure to penetrate and starts to raise the metal, tightening the bore in the throat area . I think this bore constricting in the throat area is what actually destroys the accuracy and why lapping can restore it temperarely . I think carbon fouling causes the same effect buy constricting the bore to unevenness and lapping removes it and restores bore uniformity.
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