Drop In Auto Sear Keychain File
Even if the item is made of plastic (3D printed) and would only survive one or two shots before failing, the ATF still classifies it as a machine gun. 2. Criminal Liability
Disclaimer: This article is for informational and educational purposes only. It does not constitute legal advice. Laws regarding firearms and components are complex and vary significantly by location. Always consult with a qualified attorney regarding legal matters. If you'd like, I can: involving these devices Explain the NFA classification process Compare 3D printed vs. metal components
The ATF maintains a strict interpretation of what constitutes a machine gun under the and the Gun Control Act (GCA) . Drop In Auto Sear Keychain
In recent years, various online retailers and novelty manufacturers have marketed items called "Drop In Auto Sear Keychains" or "Auto Sear Novelties." Marketing vs. Legal Reality
This is the provision that makes possessing a real DIAS a serious felony. Even if the item is made of plastic
Under 26 U.S.C. § 5845(b), the definition of a "machinegun" includes not only a weapon that shoots automatically but also The "Readily Convertible" Standard
: These are designed to provide a crisper, lighter, and more predictable trigger pull. Unlike an auto sear, these components do not alter the semi-automatic nature of the firearm. Upgraded Bolt Carrier Groups It does not constitute legal advice
Under the National Firearms Act (NFA) and the Gun Control Act , the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) classifies a functional auto sear as a "machine gun" in and of itself. It does not matter if the device is currently installed in a firearm or sitting by itself on a table—simple possession of an unregistered, functional auto sear carries severe federal penalties. Novelty Replicas vs. Disguised Contraband
As the bolt carrier moves forward and locks a new round into the chamber, it hits the auto sear. This automatically releases the hammer to fire the next round. This cycle repeats continuously until the ammunition runs out or the shooter releases the trigger. The Origin of the "Keychain" Loophole
The NFA regulates fully automatic weapons, short-barreled rifles, and silencers. Under this framework, any part designed and intended solely and exclusively for use in converting a weapon into a machine gun is legally classified as a machine gun itself.
The rise of affordable 3D printers has made manufacturing these devices trivially easy. Police departments across the nation have reported finding bags of 3D-printed auto sears on suspects. The ATF has explicitly addressed the "challenges posed by new technologies, like 3D printing," which are used to manufacture these devices.