It could be attributed to a build up fouling of lacquer or polymer inside the chamber when shooting, CLP that you are using is burning off, or a combination of both.  Often times when see someone running steel cased ammo just fine for many mags, then start to have problems, is that they started getting fouling build up in the chamber, then they stop shooting for a short recess with a live round in the chamber, then the next round will be a fail to extract.  The short recess lets the chamber fouling cool down, and kind of glues the casing into the chamber.          

Start with a thorough cleaning of the barrel using a bore brush and 1-pc cleaning rod, then a thorough cleaning of the chamber using a chamber brush and rod.  Once the fouling in the chamber and barrel are scrubbed loose, wipe and rinse with denatured alcohol to remove any traces of oil/grease/solvent.  Next thoroughly clean the entire bolt carrier assembly inside and out, removing any heavy carbon build up.  Then once everything is clean, lubricate the 7-lugs of the bolt and rails of the bolt carrier with Slip2000 "EWL" Extreme Weapons Lube, so it is a wet and glissening like a glazed donut.  By using a good lubricant like the Slip2000 EWL, you will reduce the friction, and if you reduce the friction it will reduce the heat, reduce the heat and you reduce the expansion of the parts, and it should run better.  Our experience with CLP is that it burns off in about 450rds and the gun will seize up to the point you have to relube.  Our experience with the Slip2000 EWL is that we have run one gun for 9K during and instructor course in 115-125 Fahrenheit heat without relubing, and in one rifle over 32K without relubing.                  

CY6
Greg Sullivan "Sully"
SLR15 Rifles
TheDefensiveEdge.com
(763) 712-0123

Throw in new/tight and maybe rough chamber that has not been self polish out via live fire with brass case ammo and cleanings, and you pretty much sum'd it up.

You are correct.  The lacquer or polymer has absolutely NOTHING to do with this problem.

The problem is from carbon residue left in the chamber because the steel cases have not "sealed" the chamber completely and it let carbon gasses coat the inside of the chamber.

More here:  Shooting Steel Cased Ammo in an AR-15

No problem shooting steel cased ammo in an AR-15.  But you need to clean the chamber very well before trying to shoot brass cased ammo, or jams will occur.

Have you checked the chamber for headspace?  We have seen many stuck Wolf cases in chambers that were too tight.  Any chance you can post a few pics of any of the problem cases, with some close up shots of the front and neck areas?

CY6
Greg Sullivan "Sully"
SLR15 Rifles
TheDefensiveEdge.com
(763) 712-0123

I believe you will find that this is a "carbon in the chamber" issue, not a lubrication issue.

Look at your first pic.  See that black ring near the base of the case?

That is carbon build up.  That is what is causing the problem, just as I noted in the post earlier in this thread where I linked my site.

Do you lube the chamber?  I do not.

No question about it.......An AR-15 will run wet and dirty, but not dry and dirty.

But your failures seem to be due to carbon build-up, not lube related.

A very little light oil (like WD-40) is a good idea.  But chambers should be "dry" when shooting.  Lube will only allow the cartridge case to loose its grip on the sides of the chamber and cause unnecessary high pressure against the bolt face.  This can actually be dangerous.

In an AR-15, the bolt, bolt carrier group etc should be "wet" with lubricant.  The chamber should be dry.

Powdered poly fouling in the chamber, and the new the rifle is, the sharper the edges are to scrap more of the poly off the cases.

When poly coated rounds are loaded and extracted, the poly coating is being scrapped off the case and this powderized size fouling ends up in the chamber.  The poly coating is not dissolved by any standard cleaning agents, so it has to be scrubbed out with a chamber brush instead.

Next in the math, is what is being used to clean the rifle.  Hoppes cleaning solvent (which leaves behind a protective residue) and CLP when mix, ends up being a kind of pine tar, and this will collect the fouling even faster.   So since the rifle is lubed with CLP (and used to clean most of the rifle as well), any cleaning solvent that you use other than CLP, should not leave behind a protective coating.



So lets break this down,

Start by cleaning the  rifle bore with something like Sweets copper solvent to remove the copper out of the barrel.  Once you have that dry patched remove from the bore, switch over to CLP  and a chamber brush to clean the chamber, and then run out dry patches again.   When you think that you have the chamber and barrel sparkly clean, chuck up a new 30 Cal cleaning mop in a drill and a few sections of cleaning rod, push some CLP on the Mop, then with a few spinning strokes deep in and out of the chamber with the mop, look at the mop to see if it has any discolor on it. 9 out of 10 times on guys that are not scrubbing the chamber correctly to remove all the chamber fouling, the mop come back out black (read end of chamber cut not correctly cleaned, with poly/power fouling still packed in that last of chamber cut.

Once you are sure that the chamber is clean, then finish cleaning the rifle with CLP as well (short of the chamber and bore, think of cleaning the rifle as more of a oil change).

As for lubing the upper receiver bearing areas, spray CLP on the inside and out of the B/C, give it a quick flick, then put the CLP wet B/C in the  upper and give the rifle a few unloaded cycles to migrate the CLP from the B/C to the upper surfaces.


Also, with poly coated ammo, every 200 round, pull the changing handle back slightly to get the bolt gas rings in front of the carrier exshaust ports, then spray a quick shot of CLP into the gas chamber of the B/C.  When the rifle is fired again, this fresh CLP will be migrated to the upper receiver bearing areas to lube them again.

Sorry, but that is absolutely false.  Poly is not the problem.

Read the AR-15 FAQs http://www.ar15.com/forums/t_3_16/503947_AR15_Ammo_Forum_FAQ.html

Huge difference between gun powder fouling and polyurethane (powerderized) fouling.

Look at these cases, and you can see that the problem is not gun powder fouling, but polyurethane fouling in the chamber that is  sintering between the chamber wall to brass cases/transferring to the brass cases at firing forming, and causing the brass cases to  have more surface bind to the chamber walls instead.





Blowby gun power fouling is nothing new from the cases not sealing off to the chamber walls fast enough, and in fact Federal have a great deal of problems with such in their first Gold medal match ammo in 223 when used in the AR rigs (solved by switching over to a semi faster burning powder); yet even with this amount of fouling that sooted the fed match cases/chambers/actions to all hell, there was never a problem with the rifles sticking cases/causing extraction problems due to such.  To add, there has even been some brass case ammo produced with what could be only called the dirtiest power ever conceived, the rifles still run fine on, don’t foul chamber choke out on such (migration of lube to the live round cases/chamber walls during live fire is more than enough to combat such fouling to keep it in check)

Simply, even light traces of any lube that finds it way on to the live rounds is more than enough to start to break down powder fouling in the chamber to help to dissolve and migrate such out of the chamber to allow the rifle to keep on running.

On the other hand, standard lubes and even the cleaning agent in CLP, does nothing to break down/dissolve polyurethane case scrapped off powderized fouling that finds it’s way into the chamber, and short of what of this can be flushed out as the case is being extracted, it needs to be scrubbed out instead.

Simply, we can agree to disagree, but having seen the amount of poly fouling in chamber from coated ammo, and the abrasion properties that it has over common gun powder fouling that standard lubes and solvents will not break down such, stand by my findings that it’s the powderized fouling of the steel ammo coatings that causes the problem over excessive gun powder fouling instead in the less tapered 223 type case shape chambers.

We will have to do that.  I'm done.

We really need a photo of the inside of your chamber for chamber conditions (if smooth, or if reamer marked instead).
And are you cleaning the chamber with a chamber brush with CLP each cleaning thoroughly to begin with, and correctly lubing the upper bearing surfaces with CLP?

If the chamber conditions are on the rougher side/reamer marked side, then as the spent case is pulled out of the chamber, these rough areas allow for more of the Poly coating to be scrapped off on ejection, causing more poly fouling and  some times even larger chunks of the poly to be pulled from the case as well (over just what is scrapped off the case on the way in by the mag lips and feed ramp edges.

In the below photo, second case up from the left, you had a huge chuck of debris (guessing chunk of poly off a case) that was between the chamber wall and case that left the tell tail sign on the case when fired.



As for round count before jams, just depends on how tight and rough your chamber is to begin with (will get better with live fire and cleanings through).  I have run coated wolf by the case through auto rigs with higher count fire polished chambers, with nothing more that relubing every few hundred rounds for the entire case run.  

On the other hand, have seen new, tighter civilian  barrels choke on on the coated ammo in less than 100 rounds. In cases like this, as long as the chamber is not reamer chatter central, live fire alone with brass case and cleaning, often clears the problem up in around 500 rounds (allows the chamber to self polish out through live firing and cleaning).

Post a photo of the chamber conditions to begin with.
Polishing the chamber may be a option if just on the slight rough/tight side, but only if the chamber is not reamer chatter/ridge or grooved to hell, hence defective to start with.

If the chamber looks anything like these, forget polishing/re-reaming, since even an exorcism and sacrificing a live chicken is not going to save the barrel.


http://www.ar15.com/forums/t_3_66/633354_What_caused_these_markings_on_the_casings_.html&page=1

Do you have a camera with a macro on it?

The photo's from the bore scope are not the best, and its the side wall conditions of the chamber that I'm trying to get a feeling if they are smooth and straight as a piece of glass, or high/lower reamer chattered instead.