Post sample machine guns can only be sold to class 3/SOT holders. What does that mean? Well, a class 3 dealer is usually a gun shop or gunsmith that is allowed to obtain and posses class 3 items. A SOT (Special Occupational Tax) holder can also manufacture class 3 items like silencers, machine guns, etc. They simply submit and report their models and inventory to the BATFE.

Post sample guns can be purchased directly from the manufacturer by C3/SOT holders. However, in order to do so, they must have a letter from a qualifying potential customer. This means someone legally allowed to own post ban guns which is only law enforcement or military. These are called "love letters." Once the letter is received and authorized, the manufacturer will ship a post sample machine gun directly to the C3/SOT holder. From there, they are allowed to use it as they would any other gun and since they paid for it, they get to keep it for as long as their C3/SOT license is valid.

Post sample guns can also be sold to other C3/SOT dealers. THEY CANNOT BE TRANSFERRED TO CIVILIANS. If you want to purchase a machine gun as a civilian, your only option is to buy a pre-ban machine gun.

In the NFA world, "post sample" means that the machine gun was built AFTER 1986. Therefore, it cannot be owned by a civilian. Post sample machine guns are only allowed to be owned by class 3/SOT holders. The purpose of having a post sample gun is for demonstration by a class 3 dealer to a law enforcement or military branch seeking to purchase machine guns.
Examples of post sample machine guns

• HK 416D
• HK MP7
• HK UMP
• FN Scar
• Modern AR-15 (fully automatic)

On the other hand, transferable means that the gun was added to the NFA registry before the 1986 cutoff date. Therefore, it can be sold and transferred for civilian ownership. Transferable guns are also called pre-ban guns. See more information on owning pre-ban machine guns.

This article will cover the basics on NFA items or as they are also called Class 3 items.  The term weapon is usually used in conjunction with Class 3 or NFA.  As you may also hear NFA weapon or Class 3 weapon.  I will refer them to items as things such as suppressors alone are not actual weapons.  While any object could be used as a weapon, a suppressor by itself is about as dangerous as a flash light.
NFA items are things that have been deemed by the BATFE as exceptions to the National Firearms Act. The 3 common items are the following:

• Silencers
• Short barrel rifles/shotguns (SBR/SBS)
• Fully automatic weapons (machine guns)

The National Firearms Act allows civilians to own the following items provided these items are also legal at the state level.  For example, silencers are legal in 39 of the 50 states.  Some states will allow short barrel rifles, but not silencers, and vice versa.  Check state laws to see exactly what is legal in your state.  Although, if you live in New York or California those states are the worst if you want any cool gun stuff. 

There are other things that are classified as NFA items.  These are called "destructive devices" and "any other weapon."  Examples of these include fully automatic shotguns, pen guns, and grenade launchers.  Those items are not cover in this article.

Let's talk paperwork...  NFA items are strictly controlled and carefully tracked.  The completion of paperwork usually takes anywhere from 6-8 months.  Each NFA item will require a check for $200 so the government can waste more of your money. Once the check is cashed and the paperwork is approved, you will receive a tax stamp proving you have satisfied the federal requirements to own such item.
There are 3 ways to apply for an NFA tax stamp. There is some controversy over which method is preferred but they are listed below. Follow the link to learn more about each method.

• Apply as an individual
• Apply as a corporation
• Apply as with gun trust