i have been dealing with this issue the last couple range sessions. after 100-200rds the chamber gets dirty with powder/oil like mixture that sticks to cases.. reduces extraction and have stovepipes and failure to eject

i clean with a chamber brush, cleaning rod with brush, hoppes #9, dry with patches, final pass with clp, dry, then dry chamber area with a patch soaked with brake cleaner

i started doing the brake cleaner patch cause i thought it was excessive oil left in chamber after cleaning causing problems. i also used a LIGHT coat of oil in upper reciever as not to oil up cartriges in the magazine

i have cleaned it with sweets before to remove copper. after the sweets i always rinsed with alohol soaked patches.  i have heard sweets can linger and heat up and cause gumming? i have cleaned with the brake cleaner and hoppes  several times since then though

What type of ammo are you using?  
It sounds more like an extractor/ejector issue than a chamber issue.  Make sure you do the ejector cleaning after every shooting session (couple drops of  your oil on the ejector button worked in with a casing then excess blown out) , then check your extractor spring tension, or just replace it.  
I don't know the ill effects, if any,  of a completely dry chamber, but know that  it will work with a semi-wet /dirty chamber area, as most do get that way.

this has happened about 3-4 trips out.

the past two trips i stripped the bolt , cleaned extractor (had a bit of gunk caked under it), did the oring trick on the spring. very light oil on it.. i also used a pick to scrape the carbon off of the part of the bolt the rim sits in

Wolf 55gr FMJ. i have brass xm193, but i shoot the wolf 95% of the time due to cost

I'm tempted to say that the ammo is the problem then. Some have very good luck with it. I personally experienced 2 kB's with the 7.62x39 (mine and a buddies brand new AK's within 5rds of each other on the line), so I steer clear of any of it.
If you stick with it, I'd keep the chamber as-is after cleaning/oiling, just a wipedown; maybe you need  to keep that microscopic lube buffer in there.
No matter what you shoot, it's going to get dirty, some ammo is just dirtier than others, and Wolf has some wierd black crud they call laquer they seal their cartridges with.
Sometimes cheap surplus is good, but trusting your $1000+ rifle to the cheapest in painted steel cased foul smelling Wolf is not the way to go,  JMHO.

I agree with the other guys.  Shoot some Brass case known quality ammo through it. Winnie White box . Walmart  55 grain. . Also is your chamber 5.56 ?  Or a wylde chamber ???? Is it a Chromed chamber ?  I have seen AR's run on wolf and some will not. I suspect the ammo. Good luck WarDawg

5.56 nato, chrome

edit: bbl reads:

"5.56 NATO 1/7 CB "
LMT?