The easiest way to remove these burs is to tumble the rings in a tumbler. Save time by threading the rings onto thick wire so they won't separate from the others during the tumbling process. Unfortunately the tumbling process won't always get rid of the burs. If they remain after tumbling you will need to manually remove them, I do this with my pliers. I put the end of the ring in the pliers and just rotate the pliers around the end until the bur is removed. This can take a lot of time particularly if a necklace has over 300 rings. Different jump ring sellers have different standards of the finish on the rings they sell. Some suppliers sell their rings with the burs already removed. And while these may be dearer to buy, I find the better quality finish is ultimately cheaper when I factor in the time to get the rings bur free.