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Questions and Answers

Final Rule - 2021R-05F

Final rule 2021R-05F amends the definition of the term “gunsmith” in 27 CFR 478.11 to include a person who places marks of identification on privately made firearms, as a regular course of trade or business with the principal objective of livelihood and profit.

The GCA provides no allowance for a mobile FFL business, and each location set forth on the issued ATF license must be where the intended activity will take place (with limited exceptions, such as conducting business at a qualifying gun show or event). A licensed gunsmith may not, therefore, travel to an individual customer’s location, even if that customer is another FFL, for the purpose of placing marks of identification on privately made firearms without violating the GCA and its implementing regulations.
 

ATF has long held that placing a serial number directly into polymer does not meet marking requirements since such serial number would be susceptible to being readily obliterated, altered or removed.
The final rule amends 27 CFR 478.92(a)(2) and explains that an acceptable method of identifying a polymer frame PMF is by placing a serial number on a metal plate that is permanently embedded into a polymer frame or receiver, or other method approved by the Director.

Licensees may not take into inventory PMFs they cannot mark pursuant to the requirements of 478.92(a)(2).

All licensees are required to mark all PMFs they acquire. Licensees may mark PMFs themselves or they may have any person, licensee or non-licensee, mark PMFs on their behalf. However, such other person may only mark a PMF on-the-spot under the direct supervision of the original federal firearms licensee (FFL). In this scenario, the person physically marking the PMF for the FFL will mark the PMF with the acquiring licensee’s abbreviated FFL number in accordance with 478.92(a)(2). In addition, a licensee who marks a PMF for the FFL who acquires the PMF need not log the PMF into its records.

Licensees have seven days to properly mark a PMF it acquires into inventory.

Licensees may mark PMFs themselves or they can take a PMF to any person, licensee or non-licensee, who has the ability to mark the PMF. However, such other person may only mark the PMF on-the-spot under the direct supervision of the original federal firearms licensee (FFL). This person shall mark the PMF with the original licensee’s abbreviated FFL number in accordance with 478.92(a)(2).

PMFs are marked “under the direct supervision” of the FFL who received or acquired the PMF when the FFL required to mark the PMF has not disposed of the PMF to the person doing the marking. In no case may the licensee who receives or acquires a PMF dispose of an unmarked PMF, whether to a licensee or non-licensee, until the firearm is properly marked, and the serial number is recorded in the record of the licensee who received or acquired the PMF.

The final rule amends 27 CFR 478.92(a)(2) and explains that an acceptable method of identifying a polymer frame privately made firearm (PMF) is by placing a serial number on a metal plate that is permanently embedded into a polymer frame or receiver, or other method approved by the Director.

A marking variance can be applied for under 478.92(a)(4), as amended, which states:
Exceptions—(i) Alternate means of identification. The Director may authorize other means of identification to identify firearms upon receipt of a letter application or prescribed form from the licensee showing that such other identification is reasonable and will not hinder the effective administration of this part.

Yes. Except for a firearm received for adjustment or repair that is returned to the person from whom it was received on the same day, any federal firearms licensee (FFL) who takes an unmarked PMF into inventory must mark the PMF in accordance with 27 CFR 478.92(a)(2).

Any cost associated with marking PMFs is to be determined by the licensee and the customer.

The final rule does not require licensees to notify ATF when a PMF has been marked. PMF marking and corresponding recordkeeping requirements ensure traceability of those PMFs should they be recovered.

Yes. Licensees who acquire PMFs into inventory for any reason, including private party transfers, are required to mark those PMFs, unless already marked by another licensee pursuant to 478.92(a)(2).

No. In cases where the acquiring FFL is contracting out marking services of PMFs to a licensed gunsmith (or unlicensed engraver), the gunsmith or engraver may only perform such engraving services on the spot under the direct supervision of the requesting FFL. The marking FFL need not record the PMF in his/her A&D records.

No.

The final rule clarifies that the definition of “firearm” includes a weapon parts kit that is designed to or may readily be completed, assembled, restored, or otherwise converted to expel a projectile by the action of an explosive. It also clarifies that the term “firearm” does not include a weapon, including a weapon parts kit, in which the frame or receiver of such weapon is “destroyed” as described in the definition “frame or receiver.” The final rule also explains that persons engaged in the business of selling or distributing weapon parts kits cannot avoid licensing, marking, recordkeeping, or other requirements to which federal firearms licensees (FFLs) are subject ‘‘by selling or shipping the parts in more than one box or shipment to the same person, or by conspiring with another person to do so.’’

Licensees who require a determination whether a weapon parts kit is a regulated firearm may contact ATF’s Firearms and Ammunition Technology Division (FATD) for a determination.

The term ‘‘receiver’’ in 478.12(a)(2) means the part of a rifle, shotgun, or projectile weapon other than a handgun, or variants thereof, that provides housing or a structure for the primary component designed to block or seal the breech prior to initiation of the firing sequence (i.e., bolt, breechblock, or equivalent), even if pins or other attachments are required to connect such component to the housing or structure.

The term ‘‘receiver’’ as stated in 478.12I shall include a partially complete, disassembled, or nonfunctional frame or receiver, including a frame or receiver parts kit, that is designed to or may readily be completed, assembled, restored, or otherwise converted to function as a frame or receiver, i.e., to house or provide a structure for the primary energized component of a handgun, breech blocking or sealing component of a projectile weapon other than a handgun, or internal sound reduction component of a firearm muffler or firearm silencer, as the case may be. The term shall not include a forging, casting, printing, extrusion, unmachined body, or similar article that has not yet reached a stage of manufacture where it is clearly identifiable as an unfinished component part of a weapon (e.g., unformed block of metal, liquid polymer, or other raw material). When issuing a classification, the Director may consider any associated templates, jigs, molds, equipment, tools, instructions, guides, or marketing materials that are sold, distributed, or possessed with the item or kit, or otherwise made available by the seller or distributor of the item or kit to the purchaser or recipient of the item or kit. The amended regulations examples that illustrate the definitions.

The term “readily” as defined in 478.11 means a process, action, or physical state that is fairly or reasonably efficient, quick, and easy, but not necessarily the most efficient, speediest, or easiest process, action, or physical state. With respect to the classification of firearms, factors relevant in making this determination include the following: (1) Time, i.e., how long it takes to finish the process; (2) Ease, i.e., how difficult it is to do so; (3) Expertise, i.e., what knowledge and skills are required; (4) Equipment, i.e., what tools are required; (5) Parts availability, i.e., whether additional parts are required, and how easily they can be obtained; (6) Expense, i.e., how much it costs; (7) Scope, i.e., the extent to which the subject of the process must be changed to finish it; and (8) Feasibility, i.e., whether the process would damage or destroy the subject of the process, or cause it to malfunction.

The absence of a serial number is irrelevant in determining whether a weapon is a firearm.

Licensees may voluntarily request a determination whether a receiver is a regulated firearm by contacting ATF’s Firearms and Ammunition Technology Division (FATD).

Under federal law, it’s not unlawful for a person who is not prohibited from possessing firearms to make a non-NFA (National Firearms Act) privately made firearm (PMF) for their own personal use.

The term “firearm” is defined in 27 CFR 478.11 to includes a weapon parts kit that is designed to or may readily be completed, assembled, restored, or otherwise converted to expel a projectile by the action of an explosive, and would not include a weapon parts kit, in which the frame or receiver of such weapon is destroyed.

Licensees may voluntarily request a determination whether a weapons parts kit is a regulated firearm by contacting ATF’s Firearms and Ammunition Technology Division (FATD).

A weapon parts kits that is determined to be a firearm shall be recorded as a “firearm” in the licensees’ A&D records and on ATF Form 4473.

No. Firearm muffler or silencer parts transferred between qualified manufacturers for further manufacture or to complete new devices, and firearm muffler or silencer replacement parts transferred to qualified manufacturers or dealers to repair existing devices, need not be marked at the time of transfer. Any new device completed with such a part must be registered by the manufacturer. See 478.12(b). A subpart of a firearm muffler or silencer that is not a component part of a complete weapon at the time sold must be identified by an individual serial number. See 478.92(a)(1)(iv).

Yes. Amended regulations at 478.92(a)(1)(v) allow manufacturers and importers to mark the component of a firearm (other than a privately made firearm (PMF)) defined as a frame or receiver prior to August 24, 2022, in the same manner as before the effective date of the final rule. The final rule makes clear that almost all firearms ATF previously classified as falling within the definition of ‘‘frame or receiver’’ prior to issuance of the final rule are grandfathered and may continue to be marked in the same manner as before the effective date of the final rule. The only exceptions are certain ATF classifications of partially complete, disassembled, or nonfunctional frames or receivers.

If more than one part of a silencer attaches to the barrel, each part must be marked. However, if there are multiple segmented parts, only the parts that can be attached directly to the barrel must be marked. 478.12(b) states in the case of a firearm muffler or firearm silencer, the part of the firearm, such as an outer tube or modular piece, that provides housing or a structure for the primary internal component designed to reduce the sound of a projectile (i.e., baffles, baffling material, expansion chamber, or equivalent). In the case of a modular firearm muffler or firearm silencer device with more than one such part, the terms shall mean the principal housing attached to the weapon that expels a projectile, even if an adapter or other attachments are required to connect the part to the weapon. The terms shall not include a removable end cap of an outer tube or modular piece.

No, unless remanufactured after the enactment of the GCA, October 22, 1968.

The final rule clarifies that licensed dealers (including gunsmiths), manufacturers, and importers may conduct same day adjustments or repairs to firearms without recording them as acquisitions or dispositions, provided they are returned to the person from whom they were received on the same day. A licensed gunsmith may attach a scope (including drilling, if required) on a non-licensee customer’s firearm (not for sale or distribution) and is not required to be licensed as a manufacturer. This activity would be considered an adjustment, and if returned to the person from whom received on the same day, no entry into the acquisition and disposition record would be required. The mounting of a scope would also be considered a “customization” of the firearm, accordingly, no ATF Form 4473 is required to be completed, provided the licensee returns the firearm to the person from whom it was received. However, the firearm must be logged in the licensee’s A&D record if it is kept overnight.

The timeframe is dependent on the activity conducted:

Licensed manufacturers must mark non-NFA firearms it manufactures not later than the seventh day following the date the entire manufacturing process has ended for the weapon, or prior to disposition, whichever is sooner. See 478.92(a)(1)(vi)(A).

Licensed importers must mark imported firearms within 15 days of the date of release from Customs custody. Pursuant to §478.92, licensed importers must place all required identification data on each imported firearm if same did not bear such identification data at the time of its release from Customs custody. See 478.112(d)(2).

Licensees must mark privately made firearms (PMFs) acquired into inventory not later than seven (7) days of receipt or acquisition, or before date of disposition, whichever is sooner. 27 CFR 478.92(a)(2).

Licensed manufacturers must mark NFA firearms not later than close of the next business day following the date the entire manufacturing process has ended for the weapon or device, or prior to disposition, whichever is sooner. See 478.92(a)(1)(vi)(B).

No. The AR-15 platform has been specifically addressed in the final rule and the lower receiver will remain the regulated receiver requiring the appropriate markings. Pursuant to the final rule, 27 CFR 478.12(f)(1)(i) “[t]he receiver is the lower part of the weapon that provides housing for the trigger mechanism and hammer (i.e., lower receiver).” for the AR–15/M–16 variant firearms.

No. Records are never to be consolidated between distinct FFLs. Prior to the final rule’s effective date of August 24, 2022, licensed importers were required to maintain separate records of sale or other dispositions made of firearms to non-licensees pursuant to 478.122, and licensed manufacturers were required to maintain separate records of sales or other dispositions made of firearms to non-licensees pursuant to 478.123. Also prior to the final rule, licensed importers were permitted to consolidate their records pursuant to Ruling 2011-1, and licensed manufacturers were permitted to consolidate their records pursuant to Ruling 2016-3.

The final rule codified Ruling 2011-1 and Ruling 2016-3. However, unlike the optional rulings, the final rule amended the regulations requiring licensed importers to consolidate their records of acquisition and disposition into a single record, and licensed manufacturers to consolidate their records of acquisition and disposition into a single record.

“Remanufacturing” occurs when a new and different firearm is produced from an existing firearm (i.e., frames or receivers or complete weapons) by completing, assembling, applying coatings, or otherwise making them suitable for use. Remanufacturing cannot occur if a firearm has never entered into commerce. An example is when a licensee purchases a used firearm from another licensee or a non-licensee, then performs a manufacturing process, such as cerakoting for the purposes of sales and distribution.

Any person manufacturing firearms for the purpose of sale and distribution must be licensed as a manufacturer. Cerakoting is considered a manufacturing activity.

The final rule amends 478.92(a)(4)(iii)(A) and states in part that “Licensed manufacturers may adopt the serial number and other identifying markings previously placed on a firearm by another licensed manufacturer provided the firearm has not been sold, shipped, or otherwise disposed of to a person other than a licensee, and the serial number adopted is not duplicated on any other firearm.”

If assembling firearms from a new frames or receivers, the licensed manufacturer must mark the caliber or gauge, if any, on the firearms and, if a model is assigned, mark the model on the firearms.

Last Updated: January 21, 2026

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