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Parts for AR-15 Build: A Comprehensive Guide
Building an AR-15 rifle can be an exciting and rewarding project. Whether you’re a seasoned gunsmith or a beginner, selecting the right parts is crucial for a successful build. In this guide, we’ll explore the essential components you need to consider for your AR-15 build.
Receiver
The receiver is the heart of your AR-15 rifle, serving as the central component that holds everything together. There are two types of receivers: the lower receiver and the upper receiver.
| Lower Receiver | Upper Receiver |
|---|---|
| Contains the magazine well, trigger group, and fire control group. | houses the barrel, bolt carrier group, and gas system. |
| Available in various materials like aluminum, polymer, and steel. | Also available in aluminum, polymer, and steel, with different calibers like .223, .308, and 5.56. |
Barrel
The barrel is another critical component of your AR-15 build. It determines the rifle’s caliber, barrel length, and twist rate.
- Caliber: Common calibers include .223 Remington, 5.56 NATO, and .308 Winchester.
- Barrel Length: Standard lengths are 16 inches, but you can also find 18-inch and 20-inch barrels.
- Twist Rate: The twist rate affects bullet stability and accuracy. Common twist rates are 1:7, 1:8, and 1:9.
Bolt Carrier Group (BCG)
The bolt carrier group is responsible for cycling the action of the rifle, including feeding, extracting, and ejection of rounds.
- Material: Common materials include aluminum, steel, and titanium.
- Finish: Options include Parkerized, Cerakote, and bare metal.
- Weight: Lighter BCGs can improve the rifle’s accuracy and handling.
Gas System
The gas system is responsible for controlling the amount of gas that enters the action, affecting the rifle’s cycling and accuracy.
- Gas Block: The gas block is attached to the barrel and controls the flow of gas.
- Gas Tube: The gas tube carries the gas from the barrel to the bolt carrier group.
- Gas Key: The gas key is a metal plate that seals the gas tube to the receiver.
Handguard
The handguard provides a comfortable grip and protects the barrel from damage.
- Material: Common materials include aluminum, polymer, and carbon fiber.
- Design: Options include free-float, drop-in, and fixed designs.
- Attachment: Handguards can be attached using screws, pins, or other methods.
Stock
The stock is responsible for supporting the rifle and allowing the shooter to maintain a proper grip and stance.
- Material: Common materials include aluminum, polymer, and wood.
- Adjustability: Some stocks offer adjustable length and cheek rest height.
- Design: Options include collapsible, fixed, and telescoping stocks.
Trigger Group
The trigger group is responsible for the rifle’s trigger pull and overall shooting experience.
- Trigger: Common triggers include single-stage, two-stage, and DAO (double-action-only) designs.
- Weight: Trigger pull weight can range from 2 to 10 pounds.
- Finish: Options include polished, blued, and coated finishes.
Magazine
The magazine holds the rifle’s ammunition and is crucial