Building your own AR-15 can be a rewarding experience, allowing for customization and a deeper understanding of your firearm. Many builders opt to purchase an AR-15 kit containing all the parts except the lower receiver, which requires a separate purchase and background check due to its classification as a firearm. This guide will walk you through what to expect in a complete upper and lower parts kit, helping you navigate the process of assembling your AR-15.
Understanding the AR-15 Lower Receiver's Importance
Before diving into the components of your kit, it's crucial to understand why the lower receiver is purchased separately. The lower receiver is the serialized part of the firearm, legally considered the "firearm" itself. It's the foundation upon which all other components are built and contains the critical components for operation, including the trigger group, hammer, and fire control group. The purchase and registration of the lower receiver are subject to all applicable federal, state, and local laws and regulations.
What's Included in a Typical AR-15 Kit (excluding Lower Receiver)?
A comprehensive AR-15 parts kit (excluding the lower) will typically include all the necessary components for the upper receiver assembly and other key parts. Here’s a breakdown:
Upper Receiver Group:
- Upper Receiver: This is the top half of the firearm, housing the bolt carrier group and barrel assembly. Choose between forged or billet aluminum, considering weight and strength preferences.
- Bolt Carrier Group (BCG): This is a critical part, responsible for cycling the ammunition. Look for reputable brands known for quality and reliability. Materials like chrome-plated steel and nickel boron are common choices.
- Charging Handle: This allows you to manually cycle the bolt. A variety of styles and materials are available.
- Barrel: The barrel is where the bullet is propelled. Different barrel lengths affect accuracy, velocity, and overall weight. Consider your intended use when choosing a barrel length (e.g., 16", 18", 20"). Barrel material (e.g., chrome-lined, stainless steel) and twist rate are also important factors.
- Gas Tube: This directs gas from the barrel to the bolt carrier group, enabling the cycling action.
- Gas Block: This regulates the amount of gas entering the gas tube. Low-profile or adjustable gas blocks are common.
- Handguard/Rail System: This protects the barrel and provides mounting points for accessories like lights, lasers, and optics. Materials include aluminum, polymer, and carbon fiber.
- Muzzle Device: This is usually included unless you have a specific one in mind. Common options include flash hiders, compensators, and muzzle brakes. Note that certain muzzle devices may be restricted depending on local regulations.
Other Important Components (Often Included):
- Forward Assist: Helps to ensure the bolt is fully locked into battery.
- Ejection Port Cover: Protects the ejection port from debris.
- Dust Cover: Protects the upper receiver.
- Buffer Tube: A hollow tube that houses the buffer spring and buffer weight, situated in the lower receiver.
- Buffer Spring and Weight: These work together with the buffer tube to manage recoil.
Choosing the Right Kit: Factors to Consider
Several factors should influence your kit selection:
- Budget: Kits range significantly in price depending on the quality of components.
- Intended Use: Consider whether you'll use the AR-15 for target shooting, hunting, or self-defense, as this impacts your choice of barrel length, handguard, and other components.
- Brand Reputation: Opt for reputable brands with a history of producing reliable components.
- Compatibility: Ensure all components are compatible with each other and your chosen lower receiver.
Building Your AR-15: A Word of Caution
Building an AR-15 requires careful attention to detail and adherence to safety precautions. Improper assembly can result in malfunction or injury. If you're unsure about any step of the assembly process, seek guidance from experienced gunsmiths or consult detailed assembly guides. Always practice safe gun handling techniques. Remember to familiarize yourself with all applicable laws and regulations before purchasing or assembling any firearm.
This information is for educational purposes only. Always consult with qualified professionals and adhere to all local, state, and federal laws regarding firearms ownership and usage.
