Before ever building or buying an AR pistol, you have to go to an FFL to have the serialized lower classified to be used as an AR pistol. This comes with a tax stamp price of $200 as well. Additionally, the author claimed the way ATF defined pistols was "barrel length. Any barrel under 16 inches is considered a pistol." So, how do you handle incorrect information? The author of this piece would generally be considered an ally of ours, since this is a competitive shooter, who is clearly on the side of gun ownership. However, there was not a comments section at the end of the article.