Building your AR-15 from the ground up is a rewarding endeavor that allows you to customize the rifle according to your needs and preferences. A critical component of this build is the Lower Parts Kit (LPK), which contains essential components required for the functioning of the lower receiver. In this guide, we’ll explore what’s typically included in an AR-15 Lower Parts Kit, as well as some components that you may need to purchase separately.
Understanding the Lower Parts Kit (LPK)
An AR-15 Lower Parts Kit is designed to supply all the necessary components to complete your lower receiver. It typically includes all internal parts required for the trigger assembly and other functions. Before you start your build, it’s crucial to familiarize yourself with the various components that make up the LPK.
What’s Included in a Standard AR-15 LPK
Most ar15 lower parts kit contain the following components:
1. Trigger Assembly
The trigger assembly is a fundamental part of the LPK. It includes both the trigger and the hammer, which work together to fire the rifle. The trigger assembly generally comes pre-assembled, allowing for easier installation.
2. Safety Selector
The safety selector is a lever that allows the shooter to easily engage or disengage the safety mechanism. This component ensures that the rifle cannot be fired accidentally.
3. Pistol Grip
The pistol grip is the part of the rifle where the shooter holds with their dominant hand. Many LPKs come with a basic plastic grip, but you can easily upgrade to a more ergonomic option based on your preferences.
4. Buffer Retainer and Spring
The buffer retainer and spring are essential parts that hold the buffer in place within the buffer tube. This mechanism is necessary for the proper cycling of the rifle.
5. Trigger Guard
The trigger guard is a protective covering that prevents accidental trigger pulls. In most kits, this component is designed to fit standard lower receivers and can be made of material like aluminum or polymer.
6. Magazine Catch and Release
The magazine catch allows you to securely hold the magazine in place while shooting. The magazine release is the button fitted on the lower receiver that allows for the quick removal of the magazine when needed.
7. Take-Down and Pivot Pins
These pins secure the upper and lower receivers together. They allow for easy separation of the two components for cleaning and maintenance.
8. All Necessary Springs and Detents
LPKs also come with various springs and detents that are essential for the operability of multiple components. This often includes the buffer spring, safety detent spring, and numerous others required for the trigger and magazine catch.
What’s Not Included in a Standard AR-15 LPK
While the LPK provides many necessary components, certain parts are typically not included and must be purchased separately. These may include:
1. Lower Receiver
The lower receiver itself is not included; it must be purchased individually. This part is the serialized, legally recognized firearm.
2. Upper Receiver
If you’re building a complete AR-15, you will need to procure an upper receiver separately, as it’s not part of the lower parts kit.
3. Buffer Tube Assembly
The buffer tube, buffer, and spring are generally sold separately from the LPK. This assembly is crucial for the function of the rifle and should be chosen based on your specific requirements.
4. Stock and Stock Adapter
The stock (fixed or adjustable) is not included in the LPK. You’ll have to select one that fits your build and shooting style.
5. Enhanced Triggers
If you’re looking for a higher-quality trigger, you will need to purchase an upgraded trigger assembly separately. Many shooters opt for aftermarket options that offer smoother pulls and enhanced accuracy.
6. Charging Handle and BCG
While the LPK includes everything for the lower receiver, you will need to purchase a charging handle and bolt carrier group (BCG) separately for the upper receiver.
Conclusion
An AR-15 Lower Parts Kit is an essential part of your build, providing most of the necessary components to complete your lower receiver. Familiarizing yourself with what’s included and what’s not can help you make informed decisions as you complete your AR-15. Whether you go for a basic kit or choose components that offer enhanced performance and customization, understanding the LPK will pave the way for a successful and satisfying build. Happy shooting!