ATF Open Letter to FFLs to Clarify Application of “Frame or Receiver” Final Rule

ATF Open Letter to FFLs to Clarify Application of “Frame or Receiver” Final Rule on Certain Semiautomatic Pistol Frames.

File Photo: Polymer 80 AR15 Lower with Jig System

WASHINGTON – -( Bureau of Alcohol, Tobacco, Firearms and Explosives issued an open letter today to all federal firearms licensees regarding the application of Final Rule 2021-05F, Definition of “Frame or Receiver” and Identification of Firearms, on partially complete Polymer80, Lone Wolf, and similar semiautomatic pistol frames.

In April 2022, the Department of Justice announced a new “Frame or Receiver” final rule, which modernizes the definition of a firearm. The final rule, which went into effect in August 2022, clarifies that parts kits that are readily convertible to firearms are subject to the same regulations as firearms made by a federal firearms licensed manufacturer.

Today’s open letter clarifies to the firearm industry and the public how the August 2022 final rule addresses partially complete, disassembled, or nonfunctional semiautomatic striker-fired pistol frames or parts kits manufactured, sold, or distributed by Polymer80, Lone Wolf, and others.

Partially complete Polymer80, Lone Wolf, and similar striker-fired semiautomatic pistol frames, including, but not limited to, those sold within parts kits, are regulated by the Gun Control Act (GCA) because they have reached a stage of manufacture where they “may readily be completed, assembled, restored, or otherwise converted” to a functional frame.

This definition of “readily” applies to each classification of a partially complete frame or receiver under this rule, whether sold alone or as part of a kit; therefore, even without any associated templates, jigs, molds, equipment, tools, instructions, guides, or marketing materials, these partially complete pistol frames are “frames” and “firearms” as defined in the GCA and its implementing regulations.

“Today’s open letter is another important step in implementing the crucial public safety rule regarding privately made firearms, or Ghost Guns,” said ATF Director Steven Dettelbach. “The partially completed pistol frames described in this open letter are readily convertible to functioning firearms under the Gun Control Act. Ghost Guns can kill like other firearms if they are in the wrong hands, so they are treated as firearms under the law. This means that they must have serial numbers so that law enforcement can trace if they are used in crimes like other guns, and also that those engaged in the business of selling them must be licensed dealers and run background checks.”

If anyone remains unclear about a specific model or configuration, they may submit a request with a sample to ATF, who can only render a formal determination upon receipt of a formal request and physically examining a submitted sample.

Bureau of Alcohol, Tobacco, Firearms, and Explosives

ATF regulates the firearm industry and is the lead federal law enforcement agency with jurisdiction involving firearms and violent crimes. More information about ATF and its programs is available at

Bureau of Alcohol, Tobacco, Firearms and Explosives ( ATF )

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Deplorable Bill

“A well regulated militia, being necessary to the free state, the RIGHT of the people to keep and bear arms SHALL NOT BE INFRINGED.” The second amendment to the United States of America constitution, THE law of the land. The ONLY legal business that the government has in dealing with firearms, frames, destructive devices and anything else a militia might use is SHALL NOT INFRINGE The atfe along with many other alphabet government agencies, potus and most of congress are hell bent upon destroying our GOD given, constitutionally protected freedoms and rights. They are a disgrace to the office they… Read more »

Ansel Hazen

But when a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security.

Deplorable Bill

Ahh, the declaration of independence! Governments job is to protect the welfare of the people, to guarantee and further their GOD given and their constitutional rights. Among these rights are life, liberty, the pursuit of happiness, the right to keep and bear arms, to speak your mind, to vote your conscience etc. “That to secure these rights governments are instituted among men–deriving their just powers from THE CONSENT of the governed, that whenever any form of government becomes destructive of these ends it is the right OF THE PEOPLE to alter or abolish it…” It also reads how people will… Read more »


When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature’s God entitle them… and it’s about that time, folks.

Last edited 29 days ago by Arizona

Of course, no mention that “modernizing” a definition is outside the prevue of an enforcement arm of an administrative branch, and reserved only for the legislative (as defined by the referenced GCA), which makes this “Final” rule a blatant overreach and abuse of power.

Hopefully, the lawsuits that this opens the ATF up to will point this out?

Last edited 29 days ago by willheavy

Defy, defy, defy, defy, DO NOT COMPLY. EVER. PERIOD! Kill all they send!

ONLY A TRAITOR would work for atf.

F*CK atf and their extended families!!!!! Ammoland should stop advertising for them.


F atf!


So I read this as even 80% items must be serialized per the ATF. Also seems to be limited to “striker-fired” items. So I guess serialization requirement would not apply to an aluminum 80% item. This is a very weird interpretation of a “regulation”! I sure hope the pending lawsuits jam this stuff down the throats of the BATF folks! oh, and do it quickly!


Play it again, Sam….for the Slo Joe types among us.
Politicians with laws never stop bad guys with guns.
They only control the good guys, which is their true agenda.
Unlike un-serialized firearms, serialized firearms were not in common use in 1791, therefore cannot be legal……


until 1968 even military “serialized” guns were just contract numbers, and often several makers had same numbers


Interesting how they drop this letter when multiple companies have a lawsuit in the 5th circuit and are seeking an injunction against enforcement of this rule and they will most likely succeed.


Apparently they are referring to striker style pistols only. I see nothing about AR style 80% lowers. The previous rule stated 80% receivers could be sold, just not with a jig.


my take on this as well.


Once upon a time, a maker of 80% AR type frames made what he called a 0% lower. It looked like a solid aluminum brick.

Great fun!


The next version of the tabletop cnc machine will be able to convert a block of aluminum into a lower


When are the States going to assert their rights under the 10th Amendment and tell the Washington bureaucracy to go pound sand?


I would really prefer to see states secede.


Ain’t nobody going to to jack sh*t about this. Therefore the only thing that is going to happen we are going to lose our rights 1 rule 1 law 1 gun at a time till we are completely oppressed and subservient to the U.S. Government and its law Enforcement subsidiaries there in. there is no militia there is no “WE THE PEOPLE” no nothing. everybody can’t even get along long enough to agree on one thing. Let alone stand together against 1 entity infringing on our rights. To many gun owners depending on these useless pro gun and 2A organizations… Read more »


Ya and the Britts thaught the same thing until they pushed things to far . People will only take so much before they fight back . It starts by defying crap like this and will escalate if they start knocking on doors . Don’t fool yourself !


how many have z shaped packing strap in their tool box that cut off 1 inch insert in ar and whellah full auto or true military spec lowers drill hole insert seer and pin select fire less than 5 minutes


those ” useless ” 2A organizations depend on contributions whilre the government has unlimited funds. which organization do you support? I’ll wager none.