The Complete NFA and Suppressor Glossary: Legal & Organizational Terms 

This page will focus on legal ATF/NFA definitions, advocacy groups, important rulings or laws, and miscellaneous firearms terms. This is accompanied by another glossary of industry terms.

Firearm Industry Terminology 

The firearms industry and National Firearms Act (NFA) community are full of abbreviations and gun terminology. Taking much of its influence from military lingo, the ability to condense a slew of words into just a few letters is extremely appealing. But when half of a sentence is riddled with abbreviations and acronyms, it’s easy to feel like someone is talking a different language, and it can be difficult to decipher what someone is trying to say. 

This is not a comprehensive list, but we feel this covers most of the legal acronyms, NFA definitions, and basic gun terminology. If there are any others you didn’t see on this list that you feel should be here, let us know in the comments below! 


Short Description 

Long Description 


ATF Form 4473 or Firearms Transaction Record 

A form made by the ATF that is filled out when an individual purchases a firearm from an FFL holder.  


ATF Form 5320.20 

An application that is filled out in order to transport NFA firearms across state lines. 


ATF Final Rule 41F   

Effective July 13, 2016, 41F was a Rule formed in order to implement background checks for responsible persons. This addendum to the rule made the acquisition of obtaining a silencer equal among all parties named on a gun trust, otherwise known as responsible person. 

A&D Log 

Acquisition and Disposition Log (AKA Bound Book) 

Record used by FFL's to keep track of the firearm serial numbers that they have received and sold. By ATF regulation, this log contains where the firearm was received from, the make, model, and serial number of the firearm as well as to whom the firearm was disposed to. 



This term is used most often by firearm dealers to describe when a serial number was written into their A&D Book. See also: dispose 



This term is used – again by dealers – to indicate when the firearm left their possession. See also: acquire 


American Suppressor Association 

The ASA unites, advocates, educates, and lobbies for suppressor rights, manufacturers, distributors, dealers, and consumers alike. Focusing on dispelling common misconceptions, lobbying for NFA modernization, and streamlining processes, the ASA continues to serve the suppressor community and unite this industry's efforts. 


Bureau of Alcohol, Tobacco, Firearms and Explosives 

A branch of the Department of Justice, the ATF is responsible for the investigation and prevention of offenses pertaining to alcohol, tobacco, firearms, and explosives. The ATF also regulates the sale, possession, and transportation of firearms, ammo, and explosives through specific licensing.  


Silencer Shop's Buy-It-Local Program 

A sub-set of our dealer programs, Buy-It-Local dealers are listed on our class 3 finder and able to sell products on our site. The biggest difference between PBSS and BIL is that in BIL, the Form will be filled out by the FFL instead of Silencer Shop. 

Class 3 

Class 3 License 

While often used to describe NFA firearms, this is actually a reference to the specific type of SOT license that permits FFL's to sell NFA weapons. Contrary to popular belief, Class 3's can only be obtained by FFL holders. Individuals looking to purchase “class 3 weapons” fill out a Form 4, not a Class 3 license. 

See also: Title 2. 


Chief Law Enforcement Officer 



Congressional Sportsman's Foundation 

Highly regarded in the political realm, the CSF "works with Congress, governors, and state legislatures to protect and advance hunting, angling, recreational shooting and trapping." 



The electronic system installed and controlled by the ATF for the purpose of electronically filing NFA Forms.  


Applicant Fingerprint Form 

Although you can do this on our SID kiosk, the FD258 is the government recognized physical fingerprint card that is a requirement of applying for a class 3 weapon.  


Federal Firearms Act of 1938 

The Federal Firearms Act of 1938 was the requirement of gun manufacturers, importers, and individuals in the business of selling firearms to obtain a federal license. This Act also instilled a tax on persons and entities engaged in the business of manufacturing, importing, and individuals in the business of selling NFA firearms.  


Federal Firearms License 

The license required in order to sell firearms. 


Firearm Owners' Protection Act of 1986 

The FOPA revised many of the provisions that were originally set forth in the GCA of 1968. Most often recognized as the piece of legislation that prohibited the commercial sale of newly manufactured fully automatic firearms. 

Form 1 


The Form submitted to the ATF in order for an individual/trust/corporation to create a taxable NFA item. 

Form 2 


A Form used by Class 2 SOT’s to manufacture NFA firearms.  This form is non-taxed. 

Form 3 


Used by FFL/SOT’s to allow the ability to transfer an NFA item between SOT's without tax. 

Form 4 


A taxable Form submitted to the ATF in order to transfer an NFA item between an SOT and an individuals, or between individuals.  

Form 5 


A nontaxable transfer typically to a government entity (for example, an FFL selling a destructive device to an LE agency) or sometimes used for the beneficiary of an estate after the original owner passes away. 


Firearms Regulatory Accountability Coalition 


A group fighting legal battles to strengthen the 2A.  


Gun Control Act of 1968 

The Act that regulates firearm transfers and prohibits interstate firearm transfers excluding lawful manufacturers, dealers, and importers.  


Gun Owners of America 

A pro Second Amendment advocacy group fighting to restore and protect gun laws across the country 


Hearing Protection Act of 2015 

An Act to implement the removal of suppressors from the jurisdiction of NFA, ultimately allowing suppressors to be obtained through a NICS check.  


Law Enforcement 



Military Specifications 



National Firearms Act 

An Act set in place to tax manufacturers, importers, and dealers in relation to specific firearms. The tax is enforced in the sale or disposal of those firearms.  


National Firearms Act Freedom Alliance 

The NFA Freedom Alliance was formed to ease restrictions on manufacturing, owning, selling, and using items regulated by the NFA by lobbying and working at the state and federal level. 


National Instant Criminal Background Check System 

Under the purview of the FBI, NICS determines the eligibility for an individual to purchase a firearm. The check is virtually instant and will determine whether or not the potential individual is allowed to be sold a firearm. 


National Rifle Association 

A nonprofit organization founded to advocate for gun rights and educate and teach on gun safety. The NRA was founded in 1871 and is the Nation’s longest standing civil rights organization.  


National Shooting Sports Foundation 

A foundation that is considered the firearms industry's trade association, founded in order to protect, promote, and preserve shooting sports and hunting.  


Powered By Silencer Shop 

We've teamed up with dealers around the U.S. to help you obtain your silencer even easier through this program. Read more about Powered By here! 


Responsible Person/Party 

We go into depth on what a responsible person is here, but an RP is someone assigned on your trust. Based on the definition in the trust, the responsible person generally has the same benefits as the grantor (owner) of the suppressor.  


Sporting Arms and Ammunition Manufacturers' Institute 

At the request of the federal government, this institute was formed in order to create industry standards for quality, safety, and responsibility in the use of firearms. SAAMI publishes data on ammunition that is useful in determining if a silencer is “rated” for a specific cartridge or load. 


Second Amendment Foundation 

This foundation was formed in order to shed light on Constitutional rights as well as educate and inform individuals in regard to firearms and gun control.  


Shooting, Hunting, Outdoor Trade Show 

The Mecca of tradeshows where individuals in the outdoorsy trades all convene under one roof annually to debut cool gadgets and tools. 


Secure Identity Documentation 

We talk more about it here, but to give you a brief overview, the SID kiosk helps make your Form filing life exponentially easier by digitalizing the process AND saving your information so repeating the application process for Class 3 firearms is quick and easy.  


Special Occupational Tax  

License required in order to sell Class 3 firearms in addition to FFL. 


Tax Stamp 

The holy grail. The thing you've been patiently waiting for. Otherwise known as the paperwork that allows you to obtain your device from your FFL.  

Title 1 


Otherwise known as long guns, handguns, silencers, and firearm frames or receivers.  

Title 2 


These are NFA weapons as described in Title 2 of the 1968 GCA. 


ATF spends most of their time doing 

This term is shorthand for the thorough background check done after your Form has been received.