In Simmons, the Fourth Circuit changed how one decides if a prior conviction in NC was one in which the defendant could have received a sentence greater than one year. Under NC law, the maximum penalty is determined by the class of offense and the prior record of the defendant. If the defendant could not have received more than one year for an offense because of his prior record, it does not count as a felony conviction under federal law even if the maximum sentence is greater than one year. If you have a gun case based on NC convictions for which you could not have received a sentence greater than a year, you should consult with an attorney. It is not clear if Simmons will apply retroactively, but nothing will happen if you don't raise the issue.
This answer is provided for educational purposes only and is not intended as the practice of law in any jurisdiction in which I am not licensed. The answer does not constitute legal advice nor does it create an attorney-client relationship. The answer is based only on the information provided, and may be inaccurate in the context of additional facts that have not been provided. The questioner should be aware that I am only licensed to practice law in the state and federal courts of Minnesota. Accordingly, before taking any action or refraining from taking any action, the questioner should consult with an attorney licensed to practice in his or her jurisdiction.