Drop In Auto Sear Keychain -
The ATF has repeatedly issued classification letters stating that a drop in auto sear—even one sold as a "keychain," "paperweight," or "display model"—is itself a machinegun if it is shaped and dimensioned to function as a sear.
Here is what every gun owner, collector, and 3D-printing enthusiast needs to know before this object ends up in their pocket. An "auto sear" is a component within a fully automatic firearm that catches the hammer or striker until the bolt is fully closed, allowing for "slam-fire" cycling. In a semi-automatic AR-15 platform, adding a third-pin auto sear (like a "Drop In Auto Sear" or DIAS) bypasses the trigger group's semi-auto limitation, enabling continuous firing with a single pull of the trigger. Drop In Auto Sear Keychain
At first glance, it looks like a simple piece of plastic or metal: a small, often red, oddly shaped fob meant to dangle from your keyring. However, to the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) and federal prosecutors across the United States, this "keychain" is considered a . The ATF has repeatedly issued classification letters stating
The "keychain" version is a miniature, often non-functional-looking replica of that sear. It usually includes a hole for a keyring. Some are 3D-printed plastic; others are milled aluminum or steel. Under the National Firearms Act (NFA) of 1934 and the Gun Control Act of 1968, the legal definition of a machinegun includes not only the complete weapon but also " any part designed and intended solely and exclusively, or combination of parts designed and intended, for use in converting a weapon into a machinegun. " In a semi-automatic AR-15 platform, adding a third-pin