G&G Tools is a small company that makes a small number of tools specifically for cleaning AR10 and AR15 bolts.  Recently, they introduced a new product for cleaning the bolt carrier in an AR15.

The new G&G Tolls AR-15 Bolt Carrier Cleaner works without the use of solvents, relying on mechanical (scraping) to remove carbon from the surface of the carrier.  A polishing pad is then used to remove any residual carbon.

If you watch the video of the scraper in action, you can see it appears to work very well, and in a very fast manner when compared to more traditional methods of cleaning.

The Bolt Carrier Cleaner is $12.99 individually, or $39.99 with the Bolt Cleaner.