Assembling an AR Upper: A Comprehensive Guide
Assembling an AR upper is a rewarding and exciting project for anyone interested in firearms. Whether you’re a hobbyist, a prepper, or a professional, understanding the process can help you build a custom rifle that fits your needs and preferences. In this guide, we’ll walk you through the steps, tools, and considerations involved in assembling an AR upper.
Understanding the AR Upper
The AR upper is the uppermost part of an AR-15 rifle, which includes the receiver, barrel, handguard, and sights. It’s the part that houses the bolt carrier group and is responsible for the rifle’s accuracy and performance. Before diving into the assembly process, it’s essential to familiarize yourself with the components and their functions.
| Component | Description |
|---|---|
| Receiver | The receiver is the frame of the rifle and houses the bolt carrier group. It’s the part that attaches to the lower receiver and is responsible for the rifle’s operation. |
| Barrel | The barrel is the tube that guides the bullet and is responsible for the rifle’s accuracy and velocity. It comes in various lengths and calibers. |
| Handguard | The handguard is the tube that covers the barrel and provides a place to grip the rifle. It comes in various materials and designs, such as aluminum, polymer, and carbon fiber. |
| Sights | The sights are the aiming devices that help you aim the rifle. They come in various types, such as iron sights, scopes, and red dots. |
Tools and Materials Needed
Before you start assembling your AR upper, you’ll need the right tools and materials. Here’s a list of the essential items you’ll need:
- AR upper receiver
- Barrel
- Handguard
- Sights
- Receiver extension
- Carbine buffer
- Carbine buffer spring
- Bolt carrier group
- Gas key
- Hex wrenches
- AR upper receiver vise block
- Clamp
- Gun oil
Step-by-Step Assembly
Now that you have all the necessary tools and materials, let’s go through the step-by-step process of assembling an AR upper:
- Prepare the Receiver: Place the receiver in the AR upper receiver vise block and secure it with the clamp. Apply a small amount of gun oil to the receiver extension and buffer tube.
- Install the Buffer Tube: Slide the buffer tube into the receiver extension until it seats properly. Make sure the buffer tube is flush with the receiver extension.
- Install the Buffer and Spring: Place the carbine buffer into the buffer tube, followed by the buffer spring. Ensure that the spring is fully compressed and seated in the buffer tube.
- Install the Bolt Carrier Group: Place the bolt carrier group into the receiver, ensuring that the gas key is properly seated. Use a hex wrench to secure the bolt carrier group in place.
- Install the Barrel: Slide the barrel into the receiver, ensuring that the gas port is aligned with the gas key. Secure the barrel nut with a hex wrench, but do not overtighten it.
- Install the Handguard: Slide the handguard onto the barrel, ensuring that it’s properly seated. Secure the handguard with the appropriate hardware, such as screws or pins.
- Install the Sights: Mount the sights to the handguard, following the manufacturer’s instructions. Ensure that the sights are properly aligned and functioning.
- Final Inspection: Check the assembly for any loose or improperly installed parts. Apply a small amount of gun oil to the bolt carrier group, barrel, and handguard.
