The picture isn’t very good, but you can hopefully see what appears to be a ring of carbon buildup on the bevel of the chamber face going into the chamber. I’ve been using the chamber brush on it over and over with CLP, but I can’t seem to get it off for the life of me. It’s almost making me wonder if it’s a chrome lining bare spot. I’ve shot about 300 rounds. Any advice?
[Not sure if this should be in GD or Technical]
Shoot more, clean less.
Just shoot your gun
That pic is not helpful. Either way, you should really not obsess over it.
I realize the pic sucks. Took it with a potato and can’t get a good view of it. Basically it’s a ring of carbon buildup on the face of the chamber. I suppose it’s not a problem right now but I’m about to put 1k rounds through it this weekend and don’t want it to get too built up. Sounds like it’s not a big deal though.
Lube. Shoot. Repeat.
Read this. Please. It will help you. http://www.slip2000.com/blog/s-w-a-t-magazine-filthy-14/
Are you planning on putting your rifle in a safe for years and years without handling it? Then don’t begin to worry about where there is carbon buildup. It is self limiting almost everywhere in the entire system and will simply not change the reliability.
Destroying shit via overzealous cleaning on the other hand? I make no promises.
If you’re dead set on being anal retentive and using a chamber brush, wrap the little copper lug cleaner part in a 12gauge cotton patch. Pump it in a couple of times with a little twist and trust that you’re done…because you are. A long q tip if you are simply medically required to indulge some sort of OCD.
Also, your rifle is fine. You don’t need new barrels, you don’t need to clean it within an inch of its life, and in all likelihood you’re going to **** it up. Shoot it. Lube it. Do that until your bolt breaks or the damn thing key holes and enjoy it as a tool that works in incredibly awful conditions with remarkably low maintenance. You can lube the damn thing with Vaseline and it will run. It isn’t fragile and it isn’t some precise thing that requires dental tools, crazy cleaning gear, or anything else.
I think the ring you’re talking about will be self limiting. As the bolt closes it will knock excess carbon off.
To answer your question, a steel dental type pick would scrap that off.
You’re a bad man- A real bad man
It looks like a thin layer of discoloration that won’t affect anything. This type of discoloration is normal, and you can expect more of it as you continue to use your rifle. I think you’re obsessing over this a bit too much.
Try a Dremel w/ sanding wheel if you are that OCD.
Hopefully you are getting some training this weekend and not just pumping 1K into a berm to make sure it’s “reliable” before obsessive cleaning drills. 
…and you’re just plain evil
O damn -if you only knew how that line really creeps me out when little dude says it- I literally cant stand it!!
I/we know it aint needed, but I just succinctly answered him of one way. A GI chamber brush will clean all that needs cleaned.
Carburetor cleaner. Works great. Leaves it dry and then you just lube it down.
A wet carbine is a happy carbine. Just like 51% of the population - paraphrasing Pat Rogers.
When I was in the Marine Corps, we were instructed to clean our rifles until there wasn’t a spec of dirt or carbon remaining. I didn’t know any better at the time, and took that training as gospel truth for years.
When I got out of the Marines and years later bought my first AR-15, I assumed that what I was taught in the Marines was correct. Well…I’ve come to learn otherwise from various sources.
The minor carbon that you are seeing on the face of the chamber is normal. Don’t worry about it. It’s not going to interfere with the functioning of the firearm. Focus on keeping it well lubricated. Clean the crap off of your bolt lugs periodically so that you can inspect them for wear.
This is getting to the point of “there aren’t stupid questions, only stupid people asking questions”.
I think I ****ed up. Before I even made this thread I was briefly using a brass pick to try to scrape it off, and towards the very back of the chamber I see two tiny little scratches. Can’t get a picture where they show up well. Yes I know using steel dental toothpicks and such are a no-no, but I thought that brass wouldn’t be able to scratch the chrome. I’ll take my idiot hat now.
Brass won’t scratch the steel. What you’re seeing are brass marks like the brass marks left around the ejection port.
