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ATF NPRM 2021R05 New Definitions of Frame  thumbnail image

ATF NPRM 2021R05 New Definitions of Frame

80 Percent Arms   |   Feb 9th 2022

Legal Disclaimer: The information in this blog is not legal advice. We are not lawyers. While we endeavor to keep all our blogs updated with the most accurate information, gun laws are ever changing and they can change quickly with little to complex differences in new legislation. Therefore, while we try our best to provide complete information, we acknowledge that everything you’re reading below may change (or already has changed).

Do not rely solely on the information provided by us or on this website for your purchase decisions. To ensure that you, the buyer, are acting in accordance with all federal, state laws and local ordinances, please be sure to do your own research and consult an attorney if necessary. 


*UPDATE: April 11th, 2022 — Per the 
White House statement published today, Biden had a press conference today announcing the final rule release of the ATF's 2021R-05 new proposed rulemaking on "ghost guns". See that info in complete detail there. Stay tuned for our review of this new development.

*Update: April 8th, 2022 — 
Politico released a story that states the White House will be finished with finalizing the NPRM this month and that the official announcement can be expected as early as next Monday (April 11th).

*Update: on March 28th, 2022 President Biden announced his 
fiscal budget proposal for 2023 (which still needs to be approved by Congress) and on the same day the White House published an online statement confirming their intentions which indirectly point towards the NPRM update that we are all waiting for. You can see the White House Blog here:

White House Blog - Taking on Gun Crime and Violence

*Update: on March 4th, 2022 the New York Times reported that the ATF would finalize their decision on the NPRM 2021R-05 by EARLY APRIL and that ruling would come into effect 60 days afterwards. 

You can see the New York Times story at this link here: ATF Agency Crucial to Biden's Gun Plan

What does this mean? Based on the ATF's public calendar, it seems that they're certainly on track to meet their scheduled "Final Action" will most definitely be in June. The only question now, is what will the ATF decide on? Will they go through with their ridiculous policymaking suggestions that completely bypass the constitutional process of passing laws? We'll know in a month. Until then, we're stocking up. You should too.


If you’re subscribed to a bunch of gun industry companies. There have been a lot of headlines and urgent looking emails probably sent to your inbox in the past week. We just want to provide some clarification on what’s really happened and dissect what that potentially may mean for manufacturers like us and for customers like you.

Last fall, the ATF stated that they needed time to review all comments submitted on the Federal Register website and would provide an update for a decision by some time in January or February.

Well, that update came last week. You can see that the ATF has entered the “final ruling stage” if you look at page 357/638 on their Federal Register 2022-01-31 pdf which can be found on a government website call “govinfo.”

All that really happened was that in regards to 2021R-05 the ATF released in a long document that they’ve decided that the enforcement date of said newly proposed rulemaking would begin sometime in June of 2022, they left the exact date as 6/0/22 making it unknown to us at this time.

What does that mean for 80 lower receivers and frames?

Well, more than likely, the ATF is giving themselves about 4 more months to review the extremely large number of very thoughtful comments (249.29K in total!) from individuals and businesses engaged in the gun industry which pointed out the number of internal conflicts and extreme damage this would do to the American firearms trade as a whole.

Will the ATF backpedal a bit from the original direction they were trying to go with? That is certainly the hope. We’ve seen the ATF time and again flip flop on their own policies so that’s definitely not out of the realm of possibility. There’s probably a good reason for that as well — gun rights advocacy groups could keep them real busy drowning in paperwork from lawsuits for a very long time if they actually decided to go through with this. A single state trying to enact this sort of legislation is one thing but on a federal level, no chance! …Right?

That’s the thing, in reality we really don’t know. But it would be reasonable to assume that the anti-gunners are going to try everything in their power to make the strictest version of 2021R-05 pass through into enforceable ATF policy. Realistically speaking, the ATF could make a decision AT ANY given point from now until June of this year. That’s only four months away. If they do decide to enforce 2021R-05 as is, it would spell complete and utter chaos for the gun industry.

Proposed Rule 2021R-05 Breakdown

This is our brief breakdown of the key changes that would deeply affect the gun community if 2021R-05 was to be enforced as law. For some FAQ’s on the NPRM see our company statement on the matter last year (The public commenting period deadline had passed on August 19th, 2021).

New Definition of “Firearm frame or receiver” and “frame or receiver”

Based on the new proposed rule, the ATF will consider an externally visible housing or holding structure or one or more fire control components to be considered as a frame or receiver. Examples of fire control components may include but are not limited to any of the following parts: bolt, bolt carrier breechblock cylinder, firing pin, hammer, striker, slide rails or trigger mechanism.

Does this mean AR upper receivers and slides for handguns will begin to be considered as firearms too? It’s quite possible! Which would also mean that upper receivers and handgun slides may potentially need serialization in the near future too.

What is a PMF?

A “PMF” stands for privately made firearm. Before you get mad at the buzzword, it’s certainly the more accurate term between that and “ghost guns.” Both terms refer to the same thing, essentially a homemade firearm that doesn’t have the commercial serial numbers which can be traced back to the original manufacturer or the various avenues it was sold by or transferred through.

New Marking Requirements for Silencers

The ATF just loves putting markings on everything. Based on the proposed rule, the ATF will begin to define any housing or holding structure for one or more essential internal components of a suppressor device, including, but not limited to, baffles, baffling material or an expansion chamber — as a silencer. Going forward, manufacturers would have to mark multiple predetermined parts of an actual silencer (the ATF has not yet said which components those would be). That also means a lot of muzzle device products currently on the market would potentially become silencers even though they may do nothing to suppress the sound of a bullet leaving the barrel of a firearm.

Gunsmith services

Due to the ATF requiring all PMF’s to be serialized, they’ve also anticipated the need for builders to have to go to companies or gunsmiths who offer engraving services. Well, in order for said gunsmith to offer solely this service legally, they’d have to pay an outrageously high fee in order to have a special license to legally operate and they would not be authorized to perform any repairs, modifications, embellish, refurbish or install parts in or on firearms (frames, receivers, or otherwise). To legally offer any of the aforementioned services would require a Type 07 manufacturer FFL license.

How to have a legal “PMF”

The process has not been finalized yet, but generally speaking it seems it would be similar to how residents in California have to submit an application for a firearm’s custom serial number (which they really do give out) and there would be a 60-day window for the builder to have their PMF be serialized by a licensee. Once serialized with the custom or official serial number provided or approved by the ATF, picture proof would have to be provided in order to finalize the process. Proper recordkeeping would also be required on the gunsmith’s side of things.

How you can help!

Once any development has been made on this topic, you can be sure that we will be among the first to know and you will be informed as soon as we are. We encourage everyone to take advantage of their Second Amendment rights with 80 Percent Arms. Unfortunately, if you’re just learning about this issue now, the opportunity to submit a formal comment has passed. But what you can do to help is one of three things:

1- Contact your elected representatives that you oppose 2021R-05 and want to know what your representatives plans or thoughts on the matter are.

2- Donate funds to support gun rights advocacy groups such as the Firearms Policy Coalition or Gun Owners of America.

3- Build more guns! Purchase and build your own 80% receivers and share those experiences with others.