The AR-15, a versatile and customizable rifle, has become a favorite among firearm enthusiasts. Building your own AR-15 can be a rewarding experience, allowing you to tailor the weapon to your specific needs and preferences. This guide will walk you through the process, from selecting components to assembly, ensuring you have the knowledge to create a reliable and effective firearm.
1. Understanding the Basics
Before diving into the build, it’s essential to understand the AR-15’s basic components and their functions:
- Lower Receiver: The serialized part of the rifle, housing the trigger group and magazine well.
- Upper Receiver: Contains the bolt carrier group and barrel.
- Barrel: Directs the projectile and affects accuracy.
- Bolt Carrier Group (BCG): Cycles rounds and ensures proper function.
- Trigger Group: Controls firing mechanics.
- Stock: Provides support and stability.
- Handguard: Protects your hand from the hot barrel and offers attachment points for accessories.
2. Legal Considerations
Check local, state, and federal laws regarding firearm construction. The lower receiver is considered the firearm, so purchasing it requires a background check. All other parts can be bought without such restrictions.
3. Gathering Your Parts
When building an AR-15, you can buy a complete kit or source individual parts for more customization. Key components include:
- Lower Receiver and Parts Kit: Includes the receiver and small parts for the trigger group.
- Upper Receiver: Choose between a stripped or assembled upper.
- Barrel and Gas System: Consider length, twist rate, and gas system type (carbine, mid-length, rifle).
- Bolt Carrier Group: Ensure compatibility with your upper.
- Stock and Buffer Tube Assembly: Fixed or adjustable stocks are available.
- Handguard: Options range from drop-in to free-float, impacting accuracy and accessory attachment.
4. Tools Required
Invest in quality tools to ensure a smooth assembly process:
- Armorer’s Wrench: For tightening barrel nuts and other components.
- Torque Wrench: Ensures proper torque on critical parts.
- Roll Pin Punch Set: For installing pins.
- Vise and Receiver Blocks: Stabilizes the receiver during assembly.
- Hex/Allen Wrenches: For various screws.
- Hammer and Brass/Plastic Punches: For minor adjustments and pin installation.
5. Assembling the Lower Receiver
- Install the Magazine Catch: Insert the catch through the magazine well and secure with the catch button.
- Trigger Group: Place the trigger and hammer in the lower receiver, securing with pins.
- Safety Selector: Insert the safety selector through the receiver and install the detent and spring.
- Grip and Stock: Attach the pistol grip, securing the safety spring and detent. Install the buffer tube, buffer spring, and stock.
6. Assembling the Upper Receiver
- Barrel Installation: Secure the barrel to the upper receiver using the barrel nut. Ensure proper torque.
- Gas System: Install the gas block and tube. Align the gas port with the barrel port.
- Handguard: Attach the handguard, ensuring a firm fit.
- Bolt Carrier Group and Charging Handle: Insert the charging handle and bolt carrier group into the upper receiver.
- Muzzle Device: Attach the flash hider or muzzle brake, securing with a crush washer.
7. Final Assembly and Function Check
- Join Upper and Lower Receivers: Align and secure with takedown pins.
- Function Check: Ensure the safety operates correctly, the trigger resets, and the bolt cycles smoothly.
8. Test Firing and Adjustments
Take your completed AR-15 to a range for test firing. Verify proper cycling and make necessary adjustments to the gas system and optics.
Conclusion
Building an AR-15 is an engaging process that enhances your understanding of the firearm. With careful selection of components and attention to detail during assembly, you can create a customized, reliable, and accurate rifle. Enjoy the satisfaction of a job well done and the pride of owning a firearm you built yourself. Always prioritize safety and adhere to legal requirements throughout the process.
