Automatic weapon

An automatic firearm continuously fires rounds as long as the trigger is pressed or held and there is ammunition in the magazine/chamber. In contrast, a semi-automatic firearm fires one round with each individual trigger-pull.

Although both "semi automatic" and "fully automatic" firearms are "automatic" in the technical sense that the firearm automatically cycles between rounds with each trigger pull, the terms "automatic weapon" and "automatic firearm" are conventionally reserved by firearm enthusiasts to describe fully automatic firearms. Use of this convention can avoid confusion. Firearms are further defined by the type of firearm action used.

The speed of fully automatic firearms is measured in rounds per minute (RPM) or rounds per second (RPS), in what is called the rate of fire. The speed of fully automatic firearms is compared to each other this way.

Automatic firearms can be divided into six main categories:

Automatic weapons tend to be restricted to military and police organizations in most developed countries that permit the use of semi-automatic firearms. Where automatic weapons are permitted, restrictions and regulations on their possession and use may be much more severe than for other firearms. In the United States, taxes and strict regulations affect the manufacture and sale of fully automatic firearms under the National Firearms Act. A prospective user must go through an application process administered by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), which requires a federal tax payment of $200 and a thorough criminal background check. The tax payment buys a revenue stamp, which is the legal document allowing possession of an automatic firearm. The use of a gun trust to register with the BATFE has become an increasingly popular method of acquisition and ownership of automatic firearms.

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Wikipedia