National Firearms Act
The National Firearms Act (NFA), 72nd Congress, Sess. 2, ch. 757, 48 Stat. 1236, enacted on June 26, 1934, currently codified as amended as I.R.C. ch. 53, is an Act of Congress in the United States that, in general, imposes a statutory excise tax on the manufacture and transfer of certain firearms and mandates the registration of those firearms. The Act was passed shortly after the repeal of Prohibition. The NFA is also referred to as Title II of the Federal firearms laws. The Gun Control Act of 1968 ("GCA") is Title I.
All transfers of ownership of registered NFA firearms must be done through the federal NFA registry. The NFA also requires that transport of NFA firearms across state lines by the owner must be reported to the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF, or BATFE).
The purpose of the NFA was to regulate what were considered "gangster weapons" such as machine guns and short barreled shotguns. Originally, pistols and revolvers were to be regulated as strictly as machine guns; towards that end, cutting down a rifle or shotgun to circumvent the handgun restrictions by making a concealable weapon was taxed as strictly as a machine gun.
Conventional pistols and revolvers were ultimately excluded from the Act before passage, but other concealable were not: the language as originally enacted defined an NFA "firearm" as:
A shotgun or rifle having a barrel of less than eighteen inches in length or any other weapon, other than a pistol or revolver, from which a shot is discharged by an explosive if such weapon is capable of being concealed on the person, or a machinegun, and includes a muffler or silencer for any firearm whether or not such a firearm is included in the foregoing definition.
Under the original Act, NFA "" were machine guns, short-barreled rifles (SBR), short-barreled shotguns (SBS), any other weapons (AOW or concealable weapons other than pistol or revolver) and silencers for any type of firearm NFA or non-NFA. Minimum barrel length was soon amended to 16 inches for rimfire rifles and by 1960 had been amended to 16 inches for centerfire rifles as well. In recent years several SBRs, Winchester and Marlin "trapper" rifles made before 1934 with 14 or 15 inch barrels, were removed from the NFA (Title II), although they are still subject to Gun Control Act of 1968 (Title I).
In 1938 Congress recognized that the Marble Game Getter, a short .22/.410 sporting firearm, had "legitimate use" and did not deserve the stigma of "gangster weapon" and reduced the $200 tax to one dollar for the Game Getter. In 1960 Congress changed the transfer tax for all "any other weapon" (AOW) category to $5. The transfer tax for machine guns, silencers, SBR and SBS remained at $200.
The United States Supreme Court, in 1968 decided the case of Haynes v. United States in favor of the defendant, which effectively gutted the National Act of 1934. As one could possess an NFA firearm and choose not to register it, and not face prosecution due to Fifth Amendment protections, the Act was unenforceable. To deal with this, Congress rewrote the Act to make registration of existing impossible except by the government (previously, an existing firearm could be registered by any citizen). In addition to fixing the defect identified in Haynes, the revision tightened definitions of the regulated by the Act, as well as incorporating a new category of firearm, the Destructive Device, which was first regulated in the Omnibus Crime Control and Safe Streets Act of 1968. This revision is known as the National Act of 1968 to differentiate it from the NFA of 1934, which is a different (and now void) law.
NFA categories have been modified by laws passed by Congress, rulings by the Department of the Treasury and regulations promulgated by the enforcement agency assigned to known as the Bureau of Alcohol, Tobacco, Firearms and Explosives or BATFE.
Categories of firearms regulated 
The National Firearms Act of 1968 (NFA) defines a number of categories of regulated firearms. These weapons are collectively known as NFA firearms and include the following:
Machine guns—this includes any firearm which can fire more than 1 cartridge per trigger pull. Both continuous fully automatic fire and "burst fire" (i.e., firearms with a 3-round burst feature) are considered machine gun features. The weapon's receiver is by itself considered to be a regulated firearm.
Short-barreled rifles (SBRs)—this category includes any firearm with a buttstock and either a rifled barrel under 16" long or an overall length under 26". The overall length is measured with any folding or collapsing stocks in the extended position. The category also includes firearms which came from the factory with a buttstock that was later removed by a third party.
Suppressors —this includes any portable device designed to muffle or disguise the report of a portable firearm. This category does not include non-portable devices, such as sound traps used by gunsmiths in their shops which are large and usually bolted to the floor.
Destructive Devices (DDs)—there are two broad classes of destructive devices:
- Any firearm with a bore over 0.50 inch except for shotguns or shotgun shells which have been found to be generally recognized as particularly suitable for sporting purposes. (Many firearms with bores over 0.50" inch, such as 12-gauge shotguns, are exempted from the law because they have been determined to have a "legitimate sporting use".)
Any Other Weapons (AOWs)—this is a broad "catch-all" category used to regulate any number of firearms which the BATFE under the NFA enforces registration and taxation. Examples include, among others:
1) Smooth-bore pistols 2) Pen guns and cane guns 3) A firearm with combinations smooth bore and rifle barrels 12 inches or more but less than 18 inches in length from which only a single shot can be made from either barrel. 4) Disguised firearms 5) Firearms that can be fired from within a wallet holster or a briefcase 6) A short-barreled shotgun which came from the factory with a pistol grip and no buttstock is categorized as an AOW (smooth-bore pistol) rather than a Short Barrel Shotgun (SBS), because the Gun Control Act describes a shotgun as, "…designed or redesigned to be fired from the shoulder…" 7) Handguns with a forward vertical grip.
Firearm category classifications 
The AOW listing is one area of legal debate with respect to the addition of the foregrip to a handgun/pistol. BATFE has held that it is illegal to place an aftermarket foregrip on any pistol/handgun without first registering it as an AOW and paying the $200 "making tax" imposed by the National Firearms Act (NFA). BATFE has made the decision that a handgun (but not a machine gun, since a machine gun is not also legally an AOW) with more than one hand grip at an angle to the bore is an AOW. BATFE reasoning is based on the firearm: a) being concealable on the person, and b) not meeting the definition of a "pistol" in the regulations promulgated under the NFA (not the Gun Control Act of 1968 [GCA] where the definition in law resides for a handgun/pistol), as BATFE deems a pistol/handgun is a firearm with a single grip at an angle to the bore. However, two federal cases exist that counter this finding.
At least one federal magistrate has decided that if the grip is added later, the gun is not "originally designed" to be fired by holding with more than one grip, and thus putting a second grip on a handgun/pistol does not make it an AOW. BATFE does not regard the decision as binding. The case is United States. v. Davis. The prosecution was dismissed at the request of the Government before any review of that determination by the trial judge.
Regulations promulgated at 27 CFR 478.11 provide the following definitions:
- (a) Any firearm which has a short stock and is designed to be held and fired by the use of a single hand; and (b) Any combination of parts from which a firearm described in paragraph (a) can be assembled.
- A weapon originally designed, made, and intended to fire a projectile (bullet) from one or more barrels when held in one hand, and having (a) a chamber(s) as an integral part(s) of, or permanently aligned with, the bore(s); and (b) a short stock designed to be gripped by one hand and at an angle to and extending below the line of the bore(s).
- Semiautomatic pistol.
- Any repeating pistol which utilizes a portion of the energy of a firing cartridge to extract the fired cartridge case and chamber the next round, and which requires a separate pull of the trigger to fire each cartridge.
Therefore, no wording exists in the GCA or NFA that states the addition of a vertical foregrip to a handgun/pistol originally designed to be held with one hand is an AOW. BATFE, however, still maintains the stance that such an action is enforceable under NFA. BATFE's position was formalized in April 2008 in their NFA Handbook (ATF Publication 5320.8 April 2008) which classifies an AOW as follows:
- 2.1.5 Any other weapon.
- Firearms meeting the definition of "any other weapon" are weapons or devices capable of being concealed on the person from which a shot can be discharged through the energy of an explosive. Many "any other weapons" are disguised devices such as penguns, cigarette lighter guns, knife guns, cane guns and umbrella guns. Also included in the "any other weapon" definition are pistols and revolvers having smooth bore barrels designed or redesigned to fire a fixed shotgun shell. While the above weapons are similar in appearance to weapons made from shotguns, they were originally manufactured in the illustrated configuration and are not modified from existing shotguns. As a result, these weapons do not fit within the definition of shotgun or weapons made from a shotgun. The "any other weapon" definition also includes specifically described weapons with combination shotgun and rifle barrels 12 inches or more but less than 18 inches in length from which only a single discharge can be made from either barrel without manual reloading. The firearm most commonly associated with this portion of the definition is the Marble's Game Getter. The "any other weapon" definition excludes weapons designed to be fired from the shoulder that are not capable of firing fixed ammunition or a pistol or revolver having a rifled bore. However, certain alterations to a pistol or revolver, such as the addition of a second vertical handgrip, create a weapon that no longer meets the definition of pistol or revolver. A pistol or revolver modified as described is an "any other weapon" subject to the NFA because the weapon is not designed to be fired when held in one hand. As stated above, a pistol or revolver having a rifled bore does not meet the definition of "any other weapon" and is not subject to the NFA. It is important to note that any pistol or revolver having a barrel without a rifled bore does not fit within the exclusion and is an "any other weapon" subject to the NFA.
Various legal experts argue[who?] that BATFE's position/enforcement is tantamount to illegal taxation on items which have no wording in either the GCA or NFA while BATFE maintains that it is exercising its authority granted to it by Congress under the Department of Treasury in its enforcement of the NFA.
Suppressor parts, Machine Gun Sears, and other parts associated with NFA items 
In general, certain components that make up an NFA item are considered regulated. For example, each baffle inside a suppressor, if removed from the tube, is considered a suppressor. Such suppressor parts may be legally possessed only by Class-II manufacturers. An individual cannot repair a suppressor, which must be returned to a Federal Fiream License holder (FFL) who has status as a Class-II/Special Occupation Taxpayer (SOT) manufacturer for repairs. Thus, individuals not licensed with BATFE cannot legally own any part of a suppressor without registering it with the BATFE and paying NFA taxes before construction of said item. Suppressor is the term used within the trade/industry literature while the term 'silencer' is the term used in the actual wording of the NFA. The terms are oftentimes used interchangeably depending on the source quoted.
Suppressors and machine guns are the most heavily regulated. For example, in Ruling 81-4, BATFE declared that any AR-15 Drop-in Auto-Sear (DIAS) made after November 1, 1981 is itself a machine gun, and is therefore subject to regulation. While this might seem to mean that pre-1981 sears are legal to possess without registration, BATFE closes this loophole in other publications, stating, "Regardless of the date of manufacture of a drop in auto sear, possession of such a sear and certain M-16 fire control parts is possession of a machinegun as defined by the NFA. Specifically, these parts are listed as "(a) combination(s) of parts" designed "Solely and exclusively" for use in converting a weapon into a machinegun and are a machinegun as defined in the NFA." ATF machinegun technology letters written between 1980 and 1996 by Edward M. Owen – the then-chief of the ATF technology division defined "solely and exclusively" in all of his published and unpublished machinegun rulings with specific non-ambiguous language.
Owning the parts needed to assemble other NFA firearms is generally restricted. An individual cannot own or manufacture certain machine gun sear (fire-control) components unless he owns a registered machine gun. The M2 Carbine trigger pack is such an example of a "combination of parts" that is a machinegun in and of itself. Most of these have been registered as they were pulled from stores of surplus rifles in the early 1960s. In some special cases, exceptions have been determined to these by the BATFE. A string or shoelace that could be looped around the cocking handle of a semiautomatic firearm and then behind and in front of the trigger in such a way as to allow the firearm to be fired automatically is no longer considered a machinegun unless it is attached in this manner.
Most current fully automatic trigger groups will not fit their semi-automatic firearm look-alike counterparts – the semi-automatic version is specifically constructed to reject the fully automatic trigger group by adding metal in critical places. This addition is required by the ATF to prevent easy conversion of Title I firearms into machine guns. Additionally, some fully automatic trigger groups are also permanently modified in such a way that they can no longer be made to function as fully automatic fire control devices. The ATF has listed required manufacturing procedures for modifying these fully automatic trigger groups to make them into legal semi-automatic trigger-groups for civilian sales.
For civilian possession, all machineguns must have been manufactured and registered with the ATF prior to May 19, 1986 to be transferable between citizens. These machinegun prices have drastically escalated in value, especially items like registered sears and conversion-kits. Only a Class-II manufacturer (a FFL holder licensed to manufacture firearms or Type-07 license that has paid a Special Occupational Tax Stamp or SOT) could manufacture machineguns after that date, and they can only be sold to Government, law-enforcement, and military entities. Transfer can only be done to other SOT FFL-holders, and such FFL-holders must have a "demonstration letter" from a respective Government agency to receive such machineguns. Falsification and/or misuse of the "demo-letter" process can and has resulted in long jail sentences and felony convictions for violators.
All NFA weapons made by individuals must be legal in the State or municipality where the individual lives. The payment of a $200 "making tax" prior to manufacture of the weapon, although a subsequent transfer of AOWs after they are legally "made" is only $5. Only a Class-II manufacturer (a FFL holder licensed as a "Manufacture of Firearms" or Type-07 license that has paid a Special Occupational Tax Stamp or SOT) can manufacture NFA firearms (other than destructive devices) making-tax free.
A Destructive Device manufacturing license or Type-10 FFL holder can manufacture destructive devices making-tax free. However a type-07 license costs $150 for three years –– whereas a Type-10 destructive manufacturing license costs $3000 for three years. Both licenses still require the payment of the $500 (reduced-rate) Special Occupational Tax Stamp or SOT, (or the $1000 full tax) per year to conduct manufacturing of NFA weapons that they are respectively qualified to manufacturer. The SOT "reduced rate" applies to a business whose sales are less than $500,000 per year.
Owning both a short barrel and a legal-length rifle could be construed as intent to build an illegal, unregistered SBR. This possibility was contested and won in the U.S. Supreme Court case of United States v. Thompson-Center Arms Company. BATFE lost the case, and was unable to prove that possession of a short barrel for the specific pistol configuration of a Thompson Contender is illegal. The BATFE later released ruling 2011-4 to clarify the legal status of owning such conversion kits.
Removal of a weapon from classification as an NFA firearm, such as the reclassification of the original Broomhandle Mauser with shoulder stock from "short barrel rifle" (SBR) to a curio or relic handgun, changed its status as a Title II NFA firearm but did not change its status as a Title I Gun Control Act firearm.
Muzzle-loading firearms are exempt from the Act (as they are defined as 'Antique Firearms' and are not considered 'Firearms' under either the GCA or the NFA). Thus, though common muzzle-loading hunting rifles are available in calibers over 0.50", they are not regulated as destructive devices. Muzzle-loading cannons are similarly exempt since the law draws no distinction between the size of the muzzle-loading weapons; thus it is legal for a civilian to build muzzle-loading rifles, pistols, cannons and mortars with no paperwork. While an 'antique firearm' is not considered a 'firearm' under the NFA, some states (such as Oregon) have laws that specifically prohibit anyone from owning/obtaining an 'antique firearm' that could not otherwise own/obtain an GCA or NFA defined 'firearm' (i.e., felons, recipients of dishonorable discharge from military service, the mentally adjudicated, etc.)
Individuals or companies seeking to market large-bore firearms may apply to the ATF for a "Sporting Clause Exception." If granted, the ATF acknowledges that the firearm has a legitimate sporting use and is therefore not a destructive device. Many large safari rifle calibers, such as .585 Nyati and .577 Tyrannosaur, have such exceptions.
The phrase "All NFA Rules Apply" is commonplace. This disclaimer is usually posted in bold print from firearm dealers holding an FFL license.
Registration, purchases, taxes and transfers 
It is a common misconception that an individual must have a "Class 3 " in order to own NFA . An FFL is required as a prerequisite to become a Special Occupation Taxpayer (SOT): Class 1 importer, Class 2 manufacturer-dealer or Class 3 dealer in NFA , not an individual owner. Legal possession of an NFA firearm by an individual requires transfer of registration within the NFA registry. An individual owner does not need to be an NFA dealer to buy Title II . The sale and purchase of NFA is, however, taxed and regulated, as follows:
All NFA items must be registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). Private owners wishing to purchase an NFA item must obtain approval from the ATF, obtain a signature from the Chief Law Enforcement Officer (CLEO) who is the county sheriff or city or town chief of police (not necessarily permission), pass an extensive background check to include submitting a photograph and fingerprints, fully register the firearm, receive ATF written permission before moving the firearm across state lines, and pay a tax. The request to transfer ownership of an NFA item is made on an ATF Form 4. Many times law enforcement officers will not sign the NFA documents. There have been several unfavorable lawsuits where plaintiffs have been denied NFA approval for a transfer. These lawsuit include: Lomont v. O'Neill, Westfall v. Miller, and Steele v. National Branch. In response, Tennessee and Alaska have passed state laws which require the CLEO to execute the NFA documents. On October 28, 2010, in response to a writ of mandamus, County Chancellor Robbie Beal in Williamson County, Tennessee found that the sheriff or CLEO is not required to execute NFA documents according to the Tennessee statute, Tenn. Code Ann. 39-17-1361.
NFA items may also be transferred to corporations (or other legal entities such as a trust). When the paperwork to request transfer of an NFA item is initiated by an officer of a corporation, a signature from local law enforcement is not required, and fingerprint cards and photographs do not need to be submitted with the transfer request. Therefore, an individual who lives in a location where the chief law enforcement officer will not sign a transfer form can still own an NFA item if he or she owns a corporation. This method has downsides, since it is the corporation (and not the principal) that owns the firearm. Thus, if the corporation ever dissolves, it must transfer its NFA to the owners. This event would be considered a new transfer and would be subject to a new transfer tax.
The tax for privately manufacturing any NFA firearm (other than machineguns, which are generally illegal to manufacture) is $200. Transferring requires a $200 tax for all NFA except AOW's, for which the transfer tax is $5 (although the manufacturing tax remains $200).
Dealers who pay a special yearly occupational tax are exempt from these taxes for transfers to or from other special occupational taxpayers (SOT's). Only a Class 2 manufacturer can "make and register" a machine gun—and that gun becomes a Post May-19th, 1986 Gun—salable only to police, State, local, -Government, and the military. Low volume Class 2 manufacturers (those with sales under $500,000.00) pay the $500.00 per year SOT tax, while high sales volume Class 2's pay the full $1,000.00 SOT "ticket" price.
Transferable machine guns made or registered before May 19, 1986 are worth far more than their original, pre-1986 value. And items like registered "auto-sears," "lightning-links," trigger-packs, trunnions, and other "combination of parts" registered as machineguns before the aforementioned date are often worth nearly as much as a full registered machine gun. For instance, as of September 2008, a transferable M16 rifle costs approximately $11,000 to $18,000, while a transferable "lightning-link" for the AR-15 can sell for $8,000 to $10,000. New manufacture M-16s sell to law enforcement and the military for around $600 to $1000.
The registration or transfer process (to an individual or corporation) takes approximately 3–6 months to complete as of October 2011. Additionally, the firearm can never be handled or transported by any other private individual unless the firearm's registered owner is present. Corporations which own NFA can loan them to any employee of the corporation with a letter of permission on the corporate letterhead. NFA items owned by trusts may be legally possessed by any trustee (i.e., if a husband and wife are both trustees, either of them may use and transport the firearm without the other present).
Upon the request of any ATF agent or investigator, or the Attorney General, the registered owner must provide proof of registration of the firearm.
In a number of situations, an NFA item may be transferred without a transfer tax. These include sales to government agencies, temporary transfers of an NFA firearm to a gunsmith for repairs, and transfer of an NFA firearm to a lawful heir after the death of its owner. A permanent transfer, even if tax-free, must be approved by the ATF. The proper form should be submitted to ATF before the transfer occurs. For example, lawful heirs must submit a Form 5 and wait for approval before taking possession of any NFA item willed to them. Temporary transfers, such as those to a gunsmith or to the original manufacturer for repair, are not subject to ATF approval since they are not legally considered transfers. The ATF does, however, recommend filing tax-free transfer paperwork on all such temporary transfers, to confer an extra layer of legal protection on both the owner and the gunsmith.
Criminal conduct 
The Act makes certain conduct a criminal offense, in relation to engaging in business as a manufacturer, importer, or dealer with respect to (NFA)firearms without having registered or paid a Special Occupational Tax (SOT); receiving or possessing a firearm transferred to oneself in violation of the NFA; receiving or possessing a firearm made in violation of the NFA; receiving or possessing a firearm not registered to oneself in the National Firearms Registration and Transfer Record; transferring or making a firearm in violation of the NFA; or obliterating, removing, changing, or altering the serial number of the firearm.
Criminal penalties 
Violations of the Act are punishable by up to 10 years in federal prison and forfeiture of all devices or firearms in violation, and the individual's right to own or possess firearms in the future. The Act provides for a penalty of $10,000 for certain violations. A willful attempt to evade or defeat a tax imposed by the Act is a felony punishable by up to five years in prison and a $100,000 fine ($500,000 in the case of a corporation or trust), under the general tax evasion statute. For an individual, the felony fine of $100,000 for tax evasion could be increased to $250,000.
The United States Supreme Court has ruled in Haynes v. United States that the Fifth Amendment to the United States Constitution exempts felons—and, by extrapolation, all other prohibited possessors—from the registration requirements of the Act. However, the prohibited person can still be charged under the Gun Control Act of 1968 for being a prohibited person in possession of a (any) firearm.
The Atomic Energy Act of 1954 was amended in 2005 and includes a provision (42 U.S.C. § 2201a) to allow Nuclear Regulatory Commission (NRC) licensees and authorized contractors to possess machine guns for the purpose of providing security.
The market for NFA items 
Importation of NFA firearms was banned by the 1968 Gun Control Act which implemented a "sporting" clause. Only firearms judged by ATF to have feasible sporting applications can be imported for civilian use. Licensed manufacturers of NFA firearms may still, with the proper paperwork, import foreign NFA firearms for research and development purposes, or for government use.
The domestic manufacture of new machine guns that civilians could purchase was effectively banned by language in the Firearm Owners Protection Act of 1986 (also known as "McClure-Volkmer"). The language was added in an amendment from William J. Hughes and referred to as the Hughes Amendment. Machine guns legally registered prior to the date of enactment (i.e. May 1986) are still legal for possession by and transfer among civilians where permitted by state law. The static and relatively small number of transferable machine guns has caused their price to rise, often over $10,000, although transferable Mac-10 and Mac-11 submachine guns can still be purchased for around $3,500. Machine guns manufactured after the FOPA's enactment can be sold only to law enforcement and government agencies, exported, or held as inventory or "dealer samples" by licensed manufacturers and dealers. Machine guns made after 1986 for law enforcement but not transferable to civilian registration are usually priced only a few hundred dollars more than their semi-automatic counterparts, whereas a pre-Hughes Amendment registered machine gun that can be legally transferred commands a huge premium.
The Hughes Amendment affected only machine guns. All other NFA firearms are still legal for manufacture and registration by civilians under Form 1, and transfer of registration to civilians under Form 4 (though some states have their own laws governing which NFA firearms are legal to own there). Suppressors and Short Barreled Rifles are generally the most popular NFA firearms among civilians, followed by Short Barrel Shotguns, Destructive Devices, and "Any Other Weapons". While most NFA firearms are bought from manufacturers and transferred to civilians through a dealer, many are made by the civilians themselves after filing a Form 1 and paying the $200 manufacturing tax. In some cases the manufacture is simple (i.e., using a pipe cutter to shorten a shotgun barrel), and sometimes quite complex.
Miller case 
In 1938, the United States District Court for the Western District of Arkansas ruled the statute unconstitutional in United States v. Miller. The defendant Miller had been arrested for possession of an unregistered short double-barreled shotgun, and for "unlawfully...transporting [it] in interstate commerce from Claremore, Oklahoma to Siloam Springs, Arkansas" which perfected the crime. The government's argument was that the short barreled shotgun was not a military-type weapon and thus not a "militia" weapon protected by the Second Amendment, from federal infringement. The District Court agreed with Miller's argument that the shotgun was legal under the Second Amendment.
The District Court ruling was overturned on a direct appeal to the United States Supreme Court (see United States v. Miller). No brief was filed on behalf of the defendants, and the defendants themselves did not appear before the Supreme Court. Miller himself had been murdered one month prior to the Supreme Court's decision. No evidence that such a firearm was "ordinary military equipment" had been presented at the trial court (apparently because the case had been thrown out—at the defendants' request—before evidence could be presented), although two Supreme Court justices at the time had been United States Army officers during World War I and may have had personal knowledge of the use of such weapons in combat. The Supreme Court indicated it could not take judicial notice of such a contention.
The Supreme Court reversed the District Court and held that the NFA provision (criminalizing possession of certain firearms) was not violative of the Second Amendment's restriction and therefore was not unconstitutional.
Subsequent rulings have been allowed to stand, indicating that short-barreled shotguns are generally recognized as ordinary military equipment if briefs are filed (e.g., see: Cases v. United States), describing use of short-barreled shotguns in specialized military units.
Uncertainty after Miller and after passage of Montana House Bill 246 
The scope of the application of the Act to privately constructed firearms or devices is uncertain. Such items would normally be regulated under the Act's provisions, but are intended for private ownership only and not for sale. As the Act's application is derived from the federal legislature's Constitutionally enumerated power of regulation over interstate commerce, it is unclear how privately constructed firearms or devices built solely for personal possession (i.e., not intended to be delivered into the stream of interstate commerce) are affected by the Act. It would seem they are regulated under the Supreme Court's interpretation of Wickard v. Filburn which establishes that even activities that occur solely intrastate could have such a substantial effect upon interstate commerce that failure to regulate such commerce would defeat Congress's power to regulate interstate commerce.
In the landmark 1995 case of United States v. Lopez, the first decision in six decades to invalidate a federal statute on the grounds that it exceeded the power of the United States Congress under the Commerce Clause of the United States Constitution, the Supreme Court described Wickard v. Filburn as "perhaps the most far reaching example of Commerce Clause authority over intrastate commerce." The Supreme Court majority that decided the 2005 case Gonzales v. Raich relied heavily on Filburn in upholding the power of the federal government to prosecute individuals who grow their own medicinal marijuana pursuant to state law. In Raich, the court held that, as with the home grown wheat at issue in Filburn, home grown marijuana is a legitimate subject of federal regulation because it competes with marijuana that moves in interstate commerce. As the Court explained in Gonzalez:
Wickard thus establishes that Congress can regulate purely intrastate activity that is not itself "commercial," in that it is not produced for sale, if it concludes that failure to regulate that class of activity would undercut the regulation of the interstate market in that commodity.
Montana House Bill 246, the Montana Firearms Freedom Act, was signed into law by Governor Brian Schweitzer on April 15, 2009, and became effective October 1, 2009. This legislation declares that certain firearms and firearms accessories manufactured, sold, and kept within the state of Montana are exempt from federal firearms laws, since they cannot be regulated as interstate commerce. However, this law does not apply to a firearm that cannot be carried and used by one person, a firearm that has a bore diameter greater than 1 ½ inches and uses smokeless powder, ammunition that uses exploding projectiles or fully automatic firearms. While it is likely to face a court challenge (and specifically intended to provoke one), this Montana law would put firearms accessories such as suppressors actually made in Montana, marked "Made in Montana", and sold only to Montana citizens outside federal jurisdiction and not subject to the $200 federal transfer tax.
See also 
- "ATF Regulations Reference Guide".
- History of the National Act, Bureau of Alcohol, Tobacco & .
- Robert J. Spitzer (2009). Gun control: a documentary and reference guide. Greenwood Publishing Group. pp. 131. ISBN 978-0-313-34566-1.
- R.L. Wilson, The Official Price Guide to Gun Collecting", House of Collectibles, Crown Publishing Group, New York, 2000. Eric M. Larson, "U.S. Smoothbore Pistols Designed to Fire Shotgun Shells", pp. 68-71.
- Crim No. 8:93-106 (U.S. District Court for the District of South Carolina 1993) (Report of Magistrate, June 21, 1993), "U.S. v. Davis, Cr. No. 8:93-106, Report of Magistrate".
- "Title 27 Code of Federal Regulations".
- "ATF Publication 5320.8".
- "Nos. 97-3748, 97-3749. - UNITED STATES v. CASH - US 7th Circuit". Caselaw.lp.findlaw.com. Retrieved 2012-05-22.
- [dead link]
- "ATF Ruling 2011-4".
- "ATF Rul. 2011-4". July 25, 2011. Retrieved 2011-10-26.
- Frequently Asked Questions: Section M. - NATIONAL ACT (NFA).[dead link]
- "ATF Form 4" (PDF). Retrieved 2012-05-22.
- U.S. Court of Appeals for the Ninth Circuit (2002).
- 77 F.3d 868 (5th Cir. 1996).
- 755 F.2d 1410 (11th Cir. 1985).
- "Record Keeping". Retrieved 2011-10-26.
- 26 U.S.C. § 5861.
- 26 U.S.C. § 5871
- 26 U.S.C. § 7201.
- See .
- "OPEN LETTER TO ALL FEDERALLY LICENSED DEALERS, IMPORTERS, AND MANUFACTURERS OF FIREARMS AND AMMUNITION". Bureau of Alcohol, Tobacco, Firearms, and Explosives. 2006-01-30. Retrieved 2011-10-26.
- "42 U.S.C. § 2201a : US Code - Section 2201A: Use of firearms by security personnel". Retrieved 2011-10-26.
- Gun Law News - Firearm Owners Protection Act of 1986, retrieved 2007-09-14
- Miller, at p. 175.
- 131 F.2d 916, 922 (1st Cir. 1942).
- 317 US 111 (1942)
- Deines, Kahrin. "New Gun Law Aimed at Asserting Sovereignty", Helena Independent Record, April 16, 2009.
- Text of House Bill 246, 2009 Montana Legislature.
- "State By State". Firearms Freedom Act. 2012-01-12. Retrieved 2012-05-22.
- BATFE's National Firearms Act Handbook
- Instructions and a sample ATF Form 4 for NFA Trust transfer
- Instructions and a sample ATF Form 1 for NFA Permission to Manufacture
- Instructions and a sample ATF Form 20 for Transportation of NFA Firearms across State Lines
- NFA Owners Association
- NFA Gun Trust Legal Information & FAQ's by State