I bought a new DTI barrel I always clean the barrel before I start building an AR.This barrel will not come clean.I have worn out 5 bronze brushes and have used close to 100 patches .The bore is still as dirty as when I started.By the way it is a chrome lined barrel.I have used Butches Bore shine.7.62 solvent,Hoppes #9,Gun scrubber, Powder Blast and Breakfree plus a couple more.After I run a bronze brush and run a patch .The patch comes out black as soot.It's blacker than powder residue.I'm at a loss never if my life have I had a barrel this dirty.Any Ideas on how to clean this barrel?It's like the inside of the barrel got parkerized or something.

That's strange.
How many rounds did you put through it?

I firgured it out the solvents were eroding the brushes.Thats what caused the blackness.I used a nylon brush and  after a running a few patches down the barrel they finally came out clean

Next time try some Slip 2000 725 cleaner. It really cut down cleaning time for me on the bore. It won't harm your brushes either.

Run a couple of those yellow lead scrubber patches (Kleen-Bore)down your barrel. They will show you how 'clean' your solvents, etc. get things.

I was surprised as heck when I did this. After about 30 minutes of scrubbing and patching, I ran one of these down the bore, and it came out pitch black, with a few bullet jacket shavings in it.

Spray your brushes off with brake-clean after you are done with them.
The solvents will destroy them otherwise.

Kroil + JB bore paste = clean





Brownell's sells them together as a package deal.  

I use a mixture of 2 parts Shooter's Choice bore solvent + 1 part Kroil.  I wrap a patch around a bore brush and wet it down and send it down the bore.  Do that 2-3 times followed by 2 dry patches on a dry bore brush.  Then a dry patch well coated with JB bore cleaning compound wrapped around a bore brush with short scrubbing strokes back and forth (use a bore guide!) This really kills copper fouling.  Do that twice.  Two-three more wet patches and two-three more dry patches and you are done.  I took a long range hunting class and the instructor used a bore scope on my barrels after every cleaning session.  My old cleaning habits were not cutting it.  This method amazed me!  You could actually see the difference in the bore by using this method of cleaning. I have been using it on all my rifles since.

Iosso bore paste is all I use after a few scrubbings with a brush. Actually, I run a brush through 5 times back and forth. Then a patch with solvent, then a clean dry one. I do this 4 times, Then I follow with a patch of Iosso wrapped around a parker hale style jag, pushed back and forth in the bore ten times, followed by a clean patch. I repeat this 3 times, then run a lightly oiled patch through with Rem oil on it. If I'm going to shoot right after cleaning, I skip the lightly oiled patch. The paste will get what the brushing doesn't. I use Butchs bore shine for the bore solvent, or Benchrest, depending on what's available and cheapest at the time. Hope this helps. Oh, use bronze brushes by tipton instead of copper, and you'll get less blue on your patch.

A dirty brush will foul the bore continuously if its not cleaned routinely.
What I do is I soak my brushes in alcohol to clean them....this removes carbon fouling,oil,ammonia based solvents etc..I try to keep four or five clean brushes handy so I can rotate them as they get fouled.Once I foul the brush I drop them in the jar of alcohol and continue the cycle..
Otherwise about the only solvent I use routinely is Hoppe's No.9.Allowing it to soak in the bore for a time really helps it work well.Otherwise I just clean with a good CLP,I prefer Weapon Shield but thats me.

I'm in the same situation. I have two DTI barrels; one chromed and one not. The chrome-molly barrel was really dirty, possibly some parkerazing in it; bronze brush could not clean it. I wrapped some bronze wool around the 22 cal brush and run it wet with CLP. after about 20 passages and dry patch I was close. I fire 170 round and after 30 min of cleaning with bronze brush the barrel is like a mirror and very accurate. The chromed lined has similar thing. Dirty from the beginning and difficult to clean. I didn't want to use bronze wool on this one so I used brush only and went shooting. After 110 round today and cleaning I can still see the rough land in about 1/3 of barrel length. Cleaning it wasn't any easier than chrome-molly barrel. I hope that after more shooting it will smooth out.

WIPE-OUT FTW and give up the harmful brushes.

The best brushes I've found are these.  I buy the dozen packs for all the calibers I shoot.  They screw directly on to the Dewey rods with out needing an adapter.  I think some people try to keep a $2 brush for too long.  I save a few worn brushes to use with JB compound, but otherwise when they get worn out, throw them away.  Just my opinion.

Bob

This...



And this...

Many people will drive themselves mad (I have before) when using brushes. Brushes collect dirt and are broken down by solvent (brass ones anyways), brushes are good to use to break up fouling after running an initial patch with solvent. After that I just run a wet then dry patch and repeat until all is clean. This is especially easy with a chrome bore.