80% Lower Serialization Guide

Legal Disclaimer: While we do our best to keep these policies updated in accordance with local, state and federal laws - we recognize these legal changes happen often and many times without much news coverage or public reporting. As a result, you must do your own research to ensure you are closely monitoring the evolving legal landscape and not relying on the information contained on this site to make your decisions.

We are aware that there are some states which only have a partial ban in which some counties and perhaps not the complete state have banned products we manufacture/sell. Nevertheless, in many cases we have taken the more conservative approach to restrict shipping to whole states altogether. We apologize for any inconvenience that this may cause for our customers. 

As DIY gun building becomes more popular, an increasing number of people are showing interest in the hobby. It can feel very rewarding to complete your own AR-15, then experience the fruits of your labor at target practice.

However, for many, there are still plenty of questions that they want answered before they invest in the tools and equipment that this skill requires. Some might be easy enough to answer in an FAQ, but others require a more comprehensive guide.

Fortunately, at 5D Tactical, we have the knowledge, experience, and collaborative spirit to guide you through 80% lower serialization. Below, we answer common, relevant questions, and we provide instructions for serializing your weapon, as necessary.

Your Guide to Serializing an 80% Lower Receiver

However, before we can just dive in, we have to address the elephant gun in the safe. After all, no 80% lower receiver serialization guide is complete if it doesn’t advise you to speak with a legal professional first.

Disclaimer: 5D Tactical remains a loyal and staunch supporter of the Second Amendment, however, we are not lawyers. The information provided in this blog is meant to be a service to the public and is not meant to be taken as legal advice.

Please stay up to date with your local and state laws regarding gun control laws. If you need a definitive answer do your own research as well, otherwise, consult your own attorney.

How to Serialize an 80% Lower Receiver

Let’s begin by answering those questions.

Do You Need To Serialize Your Completed Firearm?

As of the time of writing, no. In most cases, you don’t need to serialize your completed firearm if it was constructed for private use.

When Does a Firearm Require a Serial Number?

There are two ways to answer this question. First, a firearm requires a serial number when:

• It is produced or sold by a Federal Firearms Licensee
• You live in California
• You live in Connecticut

Secondly, according to the final ruling on DOJ 2021R-05, your lower receiver may need a serial number before it’s even sold to you. As mentioned above, please refer to a legal professional for the most current and relevant information.

How Do You Get a Serial Number for Your 80 Lower in California?

So you live in CA, but you’re not an FFL; how do you receive a serial number for your lower receiver?

1. Submit a PFEC Application
2. Register on CFARS
3. Submit an USNA Application
4. Engrave Your Serial Number
5. Upload Photos to CFARS

Submit a PFEC Application

Download the Personal Firearm Eligibility Check Application. You must have the completed application notarized by a licensed California Notary Public.

Then, you must mail the notarized application package to:

Register on CFARS

Once your application is approved, you must register on the California Firearms Application Reporting System (CFARS).

Submit an USNA

On CFARS, you must submit a Unique Serial Number Application (USNA). Read the application, consult your legal advisor, complete the application, and submit it to the California Department of Justice.

Engrave Your Serial Number

Once you receive your serial number, it’s time to engrave it onto your firearm. To meet federal and California standards, the serial identifier must include:

• Serial Number
• Caliber of the weapon
• Your Name
• City and State of manufacture
• Model of the weapon

Additionally, the markings must:

• Be engraved at least 0.003 inches into the material.
• Have a text size of no less than 1/16” in height.

Upload Photos to CFARS

You must take clear pictures of your engraving and upload them to your account in CFARS. This will work as proof that you’ve completed the serialization process.

Build Your Own Guns with Guidance from 5D Tactical

If you’re a DIY gun builder, then it’s vital that you stay informed about your hobby. For more guidance on building your own guns, reach out to the 5D Tactical team today.