How To Make A Drop In Auto Sear

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Hey Hunters! In this Blog, I have discussed the auto sear system in detail. And how does one go about making a drop in auto sear?

Let’s start with the fundamentals: what is a drop in auto-sear?

The semi-automatic AR-15 weapon can be changed into a fully automatic weapon by installing an auto sear. The drop-in auto sear can be referred to as a conversion device to further clarify this term.

What material is this conversion device made of? The sear, which is a component of the trigger group and retains the hammer down until the trigger is pulled, is effectively replaced with metal.

Why would one need a conversion device? As it is an easy and affordable way to turn the rifle into a fully automatic weapon.

History Of Drop-In Auto Sears

To avert the installation of full-auto fire control components, Samuel Colt had to make modifications to the AR-15 rifle’s structure, which included extracting the pin, auto sear, and mounting holes. The drop-in auto sear was created to replace the traditional auto sear’s functionality without the addition of a mounting pin and to work with a portion of the full auto fire suppression components. It was commonly found through online ordering and unregulated. In 1981, ATF categorized the drop-in auto sear as a standalone weapon, outlawing its possession. Exemplified, though, were those created before the decision and were protected.

The weapon registry was shut down and lawfully revised in 1986 by the “Firearm Owners’ Protection Act”. Since that time, it has been prohibited to own a drop-in auto sear, though it was once lawful to register one until the Hughes Amendment closed the registry and turned it into a legal weapon. Several of these authorized drop-in auto sears are still on the registration system even now, under which their worth has continued to rise to well almost that of an exact certified M16 owing to the legal documentation.

Automatic Sear And Firearm

The phrase “automatic sear” refers to the device in a gun that changes a semi-automatic weapon into a fully automatic one. Burst mode is another possible outcome of the conversion.

What does the firearm’s fully automatic mode do? The firearm’s fully automatic mode continues firing until the trigger is set free. This means that this firearm can fire several shots at once. What does the firearm’s burst mode do? When the trigger is pulled, the burst mode firearm fires three to four shots at a moment.

So, this metal device is mounted in the firearm for a fully automatic system, even though it is illegal under US federal law. When the firearm is set to fully automatic, the sear just lets go of the striker, allowing the weapon to shoot constantly and consistently.

Types Of Automatic Searing Systems

There are two types of auto-searing systems, which are described further below.

Mechanical  auto-searing system:

  • It uses a mechanical device to sear.
  • Typically use a disk or rotating blade to sear.

Heated plate auto-searing system:

  • It uses a heated plate to sear.
  • Less expensive than mechanical searing.

Components You’ll Need And Safety Measures

Here are some components and safety precautions you should be aware of before installing the auto sear. 


The most crucial element you will need is “steel.” You will have two choices: either use the aforementioned component to make your auto sear, or purchase an auto sear that has previously been made.

Safety measures:

  • Keep the auto-sear in its proper location in the weapon. 
  • Maintain a barrier between the auto-sear and other parts of the firearms. 
  • Keep the auto-sear free of clutter and spotless. 
  • Ensure that the auto-sear is adequately greased. 
  • Ensure that children cannot access the auto-sear.

Limitations Of An Automatic Sear System

Although drop-in auto-sear conversion kits have drawbacks, they are permitted in many countries.

  • Installation of the auto-sear system is challenging.
  • It needs a few things, so the setup will take some time.
  • If not installed correctly, it might be unsafe.
  • Increase the rifle’s stress and strain because fully automatic mode shoots at a much quicker speed.
  • Drop-in auto sears are relatively expensive (under $1000).

Wrapping It Up!

Making your rifle fully automatic is possible by installing an auto-sear system. Your rifle will operate more effectively if you do it this way. However, before installing the auto-sear, remember the safety precautions I mentioned earlier. There are also a few limitations to installing the auto-sear such that it is expensive, can be dangerous if not installed properly, etc.


How exactly does drop-in auto sear operate?

When a drop-in auto sear is tried to install in an AR lower, the bolt carrier keeps moving backward, pressuring the hammer straight down and holding something that.

What does a drop in auto sear mean?

Drop-in auto sears are just an AR-15 component that, when combined with specific other components, allows for full-auto firing.

What’s the process of an auto sear?

An auto sear converts any firearm into a completely automatic weapon, enabling it to shoot over 16 rounds with a single pull of the trigger.

Can a semi-auto be converted to a full-auto?

Making your gun fully automatic is against the law according to federal regulations.

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Hannah Anderson is a gun enthusiast. She developed a knack for guns and ammunition when as a teenager she started accompanying her grandfather to his hunting ventures. Now, she shares her passion and immense knowledge on the subject with the readers.

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