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Phil3
11-02-2009, 7:16 AM
Barrel Break-In & Fouling

I built my first AR15 and took it to the range, and it worked OK, but have a question on barrel break-in. Please note, I am very new to centerfire, hence the novice question. Per Krieger’s instructions, I cleaned after each shot for the first 5 shots, and then after each group of 5 for the next 3 – 4 groups (25 rounds total), yet carbon fouling seemed severe (very black patches). I never saw any evidence of any copper fouling (copper color in interior of barrel at muzzle end), or any green color on the patch, which is what I expected. I did not expect to see the very black patches, even after just one round.

I was using TM Bore Cleaner, and later tried Butch’s BoreShine (same result). I let both sit in the barrel for a few minutes. Ammo used was PMC Bronze 55 grain FMJ.

The gun was shooting .75” groups, and a best of .625” at 100 yards, and then on one group, opened up to about 2”. I cleaned the barrel, and it got notably better. I had not cleaned the barrel for probably something like 20 rounds at this point.

How much carbon fouling is expected and am I missing the copper fouling somehow?


- Phil

Greg-Dawg
11-02-2009, 8:28 AM
What kind of barrel? Chrome lined? Chrome moly? Stainless?

ocabj
11-02-2009, 8:54 AM
My AR cleaning has evolved in the past couple years. What I do now:

1. Remove charging handle and BCG. Disassemble BCG on a mat. Spray down charging handle and BCG parts with M-Pro7.

2. With upper removed from lower, put in cradle upside down. Spray receiver channel with M-Pro 7. Use plastic bristle brush on inside to loosen fouling. Use paper towel or rag to wipe out.

3. Holding upper muzzle down into a pan or other receptacle, spray M-Pro7 into chamber a few times and let M-Pro7 drip out of muzzle. Let sit in cradle. Use chamber cleaning brush to scrub chamber and lugs. Use 12gauge mop to wipe lug recess. Use 30 cal mop to wipe chamber.

4. Insert bore guide and let upper sit for several minutes (M-Pro7 soaking in chamber).

5. Use nylon brush in barrel for several strokes.

6. M-Pro7 on patches several times until clean. This will get out pretty much all carbon fouling and some copper.

7. Dry patch when carbon fouling gone.

8. Wet patch with Montana Xtreme a few times to clean copper.

9. Dry patch when patches not blue.

10. Done with barrel. Run lightly oiled patch through barrel if not shooting anymore.

During the time I'm letting the barrel soak, I'm also cleaning the BCG parts.

I think M-Pro7 is better for quality barrels, since your main goal is to get carbon/powder fouling out. Copper fouling will be negligible in a good barrel, and even then, M-Pro7 does a decent job getting residual copper out. Then Butch's Bore Shine or Montana Xtreme will get any leftover copper.

Phil3
11-02-2009, 10:41 AM
What kind of barrel? Chrome lined? Chrome moly? Stainless?

Stainless.

Phil3
11-02-2009, 10:44 AM
My AR cleaning has evolved in the past couple years. What I do now:

1. Remove charging handle and BCG. Disassemble BCG on a mat. Spray down charging handle and BCG parts with M-Pro7.

2. With upper removed from lower, put in cradle upside down. Spray receiver channel with M-Pro 7. Use plastic bristle brush on inside to loosen fouling. Use paper towel or rag to wipe out.

3. Holding upper muzzle down into a pan or other receptacle, spray M-Pro7 into chamber a few times and let M-Pro7 drip out of muzzle. Let sit in cradle. Use chamber cleaning brush to scrub chamber and lugs. Use 12gauge mop to wipe lug recess. Use 30 cal mop to wipe chamber.

4. Insert bore guide and let upper sit for several minutes (M-Pro7 soaking in chamber).

5. Use nylon brush in barrel for several strokes.

6. M-Pro7 on patches several times until clean. This will get out pretty much all carbon fouling and some copper.

7. Dry patch when carbon fouling gone.

8. Wet patch with Montana Xtreme a few times to clean copper.

9. Dry patch when patches not blue.

10. Done with barrel. Run lightly oiled patch through barrel if not shooting anymore.

During the time I'm letting the barrel soak, I'm also cleaning the BCG parts.

I think M-Pro7 is better for quality barrels, since your main goal is to get carbon/powder fouling out. Copper fouling will be negligible in a good barrel, and even then, M-Pro7 does a decent job getting residual copper out. Then Butch's Bore Shine or Montana Xtreme will get any leftover copper.

All good stuff...thanks. What about cleaning at the range? - Phil

SJgunguy24
11-02-2009, 10:54 AM
This is a dupe but watch the video, very informitive.:D

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Fjold
11-02-2009, 11:01 AM
Carbon fouling is a function of the load more than the barrel. The reason that you are not seeing copper fouling is because you have a hand lapped barrel.

What load are you shooting? Try a different load and see how it works.

I have a Krieger in a 6.5x284 bolt gun and I never see copper in it even after 80-100 rounds and about 3-4 wet patches usually gets all the carbon out.

ocabj
11-02-2009, 11:23 AM
All good stuff...thanks. What about cleaning at the range? - Phil

Cleaning at the range? Same as I clean at home.

Phil3
11-02-2009, 11:40 AM
Carbon fouling is a function of the load more than the barrel. The reason that you are not seeing copper fouling is because you have a hand lapped barrel.

What load are you shooting? Try a different load and see how it works.

I have a Krieger in a 6.5x284 bolt gun and I never see copper in it even after 80-100 rounds and about 3-4 wet patches usually gets all the carbon out.

The ammo used was PMC Bronze 55 grain FMJ. This is not what I intend to use going forward and was only used to break in the barrel, test the rifle, and get the scope reasonably sighted in.

I have on order BlackHills remanufactured ammo FMJ in 55 grain and 69 grain (300 rounds total).

After that, I will be reloading my own.

Is copper fouling quite evident at the muzzle end? I have never seen it, so not sure what to look for.

- Phil

Phil3
11-02-2009, 11:41 AM
Cleaning at the range? Same as I clean at home.

I am not sure the bench at the range is large enough to support this much of a project. :D But, I will endeavor to do superior cleaning while there.

- Phil

ocabj
11-02-2009, 11:49 AM
Cleaning shouldn't take that much space. The size of a basic shooting bench will work fine for a working surface.

Worst case, use the tailgate of your truck/SUV if you're driving one. No one should give you static for cleaning behind the firing line if you have the upper separated from the lower.

MasterYong
11-02-2009, 12:00 PM
There's no reason to break in the barrel. Do a search, you'll find that break-in procedures are for the most part an industry con.

Try putting this into google (without the quotes):

"site:calguns.net barrel break in"

SJgunguy24
11-02-2009, 12:00 PM
Cleaning shouldn't take that much space. The size of a basic shooting bench will work fine for a working surface.

Worst case, use the tailgate of your truck/SUV if you're driving one. No one should give you static for cleaning behind the firing line if you have the upper separated from the lower.

That depends on the range Nazi's and how hard they weild the iron fist

phish
11-02-2009, 12:02 PM
Kriegers don't need no stinkin breaking in :83:

Fjold
11-02-2009, 12:31 PM
Copper fouling will show up as orange streaking in the bottom of the grooves and is pretty easy to see if you get the sun shining in the barrel.

If you use a copper cleaner it will show up as blue or green stains on your patches as you clean. You will usually see a little light green when you use a copper cleaner even on the best barrels but it should wipe out quickly and easily after couple of patches.

Phil3
11-02-2009, 1:16 PM
Kriegers don't need no stinkin breaking in :83:

They would not agree.

http://www.kriegerbarrels.com/Break_In__Cleaning-c1246-wp2558.htm

I spoke with them personally, and they said that due to the hand lapping, it would not take many shots to break in, and copper fouling, with something like a 223 Remington is likely to be minimal (I saw none). Much worse with something like a 300 WinMag according to Krieger.

- Phil

Bug Splat
11-02-2009, 1:18 PM
There's no reason to break in the barrel. Do a search, you'll find that break-in procedures are for the most part an industry con.

Try putting this into google (without the quotes):

"site:calguns.net barrel break in"

+100

Barrels don't need "breaking in". Shoot it like you stole it and clean it when you are done for the day. At the very most maybe use a bore snake to pull out the crap from dirty powder.

The few rounds you use to site in your irons or optics is enough to smooth the rifling out.

Fjold
11-02-2009, 3:03 PM
What Krieger used to say is to clean the throat where the chambering reamer cuts across the lapped finish. Scrub the throat out for the first few rounds to get the copper out of the reamer marks. The first few bullets will get the reamer marks to lay in the right direction without having any copper caught in them.

Phil3
11-02-2009, 4:19 PM
To your point, Krieger say in part this.

"...Because the lay of the finish is in the direction of the bullet travel, very little is done to the bore during break-in, but the throat is another story. When your barrel is chambered, by necessity there are reamer marks left in the throat that are across the lands, i.e. across the direction of the bullet travel. In a new barrel they are very distinct; much like the teeth on a very fine file. When the bullet is forced into the throat, copper dust is released into the gas which at this temperature and pressure is actually a plasma. The copper dust is vaporized in this gas and is carried down the barrel. As the gas expands and cools, the copper comes out of suspension and is deposited in the bore. This makes it appear as if the source of the fouling is the bore when it is actually for the most part the new throat. If this copper is allowed to stay in the bore, and subsequent bullets and deposits are fired over it; copper which adheres well to itself, will build up quickly and may be difficult to remove later. So when we break in a barrel, our goal is to get the throat polished without allowing copper to build up in the bore. This is the reasoning for the "fire-one-shot-and-clean" procedure...".