Pistol Stabilizing Brace’s Explained There's been a lot of attention given to Pistol Stabilizing Braces recently. We put this article and video together to help you understand what they're all about. THE NATIONAL FIREARMS ACT A Springfield Armory SAINT Pistol. (Photo: Recom / Guns.com) In 1934, Congress passed the National Firearms Act, or NFA. It classified a rifle as a weapon fired from the shoulder with a barrel length of 16 inches or more. Under 16 inches, it was classified as a short-barreled rifle, or SBR. Buying an SBR requires the purchase of a $200 tax stamp much like machine guns or silencers. The NFA also classified handguns as firearms with a short stock designed to be held and fired with a single hand. But handguns had no barrel length regulations. These classifications remain today.