How to use or not to use, that is the question.
The Sig Sauer SB-15 stabilizing brace for AR-type pistols has exposed some sticky legal questions. Does the use of a product define its purpose? For example, if one uses a hammer to remove a corroded battery terminal from a 1970 Gremlin, does the use redefine that same hammer as a wrench?
Historically, the BATF, citing National Firearms Act (NFA) regulations, has adhered to clear boundaries related to the design of a firearm. If a firearm fell outside of technical definitions, its manufacture and transfer was deemed subject to the terms of the NFA. For example, if a manufacturer put forth a rifle with a 12-inch barrel, it would be subject to NFA restrictions. Clear enough, right?
In the case of the Sig Sauer SB-15 Stabilizing Brace, the ATF has gotten itself into a pickle. Initially, the agency issued a ruling in favor of the Sig Sauer stabilizing brace, stating that “We find that the device is not designed or intended to fire a weapon from the shoulder. Based on our evaluation, FTB finds that the submitted forearm brace, when attached to a firearm, does not convert the weapon to be fired from the shoulder and would not alter the classification of a pistol or other firearm.”
In a subsequent open letter, the ATF appears to contradict its stance of applying NFA regulations to firearms design rather than use. According to the newest ATF letter, “Because the NFA defines both rifle and shotgun to include any “weapon designed or redesigned, made or remade, and intended to be fired from the shoulder,” any person who redesigns a stabilizing brace for use as a shoulder stock makes a NFA firearm when attached to a pistol with a rifled barrel under 16 inches in length or a handgun with a smooth bore under 18 inches in length.”