I shoot a lot of steel case ammo in my AR. I understand that the steel case does not expand as well as brass and that causes extra carbon build up in the chamber. Is there an easy or preferred way to clean the chamber out. I know the carbon build up on my bolt has to be scraped off with a knife. If it gets caked in the chamber this bad I may have to start shooting brass to prevent this build up.

Get a Chamber Brush and clean it out.

I'd go with the bronze/stainless steel chamber brush, unless you're barrel is stainless steel then I'd use the nylon one suggested above.
http://www.brownells.com/.aspx/pid=1234/Product/M16___AR_15_CHAMBER_BRUSHES

Roger roger on the chamber brushes.
However, I'm not that smart and can get the brushes to work only clockwise.....

So I have my trusty toothbrush that is soaked w/ Hoppes and clean like a dental hygienist. I let it soak (barrel too) while I multitask on the rest of the gun(s). Sometimes I use my favorite aerosol degreaser to remove the solvent and treat appropriately.....  Seems to help.