California AB 243: Ghost Gun Serial Number Requirements
Understand the legal obligations for owners of self-manufactured firearms under CA's AB 243, which mandates a state-managed serialization process.
California law regulates self-manufactured firearms, often called “ghost guns,” to ensure they are traceable by law enforcement. These regulations require individuals who build their own firearms to obtain and affix a unique serial number issued by the state’s Department of Justice (DOJ). This framework is designed to bring personally made firearms into a similar regulatory structure as commercially produced firearms. The rules apply to a wide range of firearms, from those assembled from kits to those created with 3D printers, closing a loophole that allowed for untraceable weapons.
Firearms Requiring a Serial Number
The law targets any firearm that is self-manufactured, including those built from kits or individual parts. A central component in this regulation is the “firearm precursor part.” California law defines this term as an unfinished frame or receiver that is designed to be, or can be readily converted into, the frame or receiver of a functional firearm. Common examples include 80% receivers or frames, which are partially completed but require additional milling or drilling to become operational.
This definition also encompasses firearms created using modern technology. If an individual uses a 3D printer to produce a polymer-based frame or receiver for a handgun or rifle, that component is subject to the same serialization requirements. The law is constructed to be technology-neutral, focusing on the functional outcome rather than the method of production.
Furthermore, any person who uses a 3D printer or CNC milling machine to manufacture a firearm must be a state-licensed firearm manufacturer. The law also prohibits the sale or possession of a 3D printer or CNC mill if its sole or primary purpose is to manufacture firearms, except for licensed manufacturers. For firearms made from polymer, the law includes specific requirements to ensure the serial number is durable and cannot be easily removed.
Owner Compliance Requirements
An individual’s primary responsibility is to secure a unique serial number from the California DOJ before the firearm is fully assembled. It is illegal to complete the manufacturing or assembly of a firearm without having first been issued a serial number by the state. This requirement ensures that no new, unserialized firearms are created.
As of January 1, 2024, the deadline to obtain a serial number for any previously self-manufactured firearm has passed. Consequently, the possession of an unserialized, self-made firearm or firearm precursor part is now prohibited in California.
The law also regulates the sale or transfer of firearm precursor parts. Since July 1, 2022, any sale or transfer of a precursor part, such as an 80% receiver, must be conducted through a licensed firearm precursor part vendor. This process requires a background check, similar to the process for fully assembled firearms.
Information Needed for the DOJ Application
To comply, individuals must submit an application through the California Department of Justice’s California Firearms Application Reporting System (CFARS). This online process must be completed before manufacturing or assembling a firearm. The application is used to verify the applicant’s identity and conduct a background check to confirm they are legally eligible to own a firearm.
The application requires detailed personal and firearm information, including:
- Full name, residential address, telephone number, and date of birth
- California Driver License or Identification Card number
- Firearm type, such as pistol, revolver, rifle, or shotgun
- The firearm’s caliber
- Material of the frame or receiver (e.g., polymer, aluminum, steel)
- The firearm’s color
The Application and Engraving Process
Once the application is submitted online via CFARS, it must include payment for the application fee of $46.19. This fee covers the cost of the background check and one unique serial number.
After the DOJ processes the application and confirms the applicant’s eligibility to possess a firearm, it will issue a unique serial number. This serial number is specifically assigned to the firearm described in the application and cannot be used for any other weapon. The applicant must wait to receive this official number before proceeding with assembly.
The final step is to permanently affix the serial number to the firearm. The serial number must be engraved or similarly placed onto the firearm’s frame or receiver within 10 days of completing the firearm’s assembly. Regulations specify the required size and depth of the engraving to ensure it is legible. For firearms made from polymer, the number must be engraved on a 3.7-ounce piece of 17-4 PH stainless steel embedded within the plastic frame.