AR-15 Dimensions Lower Receiver: A Comprehensive Guide
The AR-15 lower receiver is a crucial component of the popular AR-15 rifle, serving as the foundation for the firearm’s assembly. This guide will delve into the dimensions, materials, features, and legal aspects of the AR-15 lower receiver, providing you with a comprehensive understanding of this essential part.
Dimensions and Specifications
The AR-15 lower receiver is designed to fit within specific dimensions to ensure compatibility with other components. Here’s a breakdown of the key dimensions:
| Dimension | Measurement |
|---|---|
| Length | 7.25 inches |
| Width | 1.5 inches |
| Height | 1.25 inches |
These dimensions are crucial for ensuring that the lower receiver fits properly within the rifle’s frame and that other components, such as the upper receiver, magazine, and stock, can be attached without issues.
Materials Used
The AR-15 lower receiver is typically made from two main materials: aluminum and polymer. Here’s a closer look at each:
Aluminum:
Aluminum is the most common material used for AR-15 lower receivers. It offers a good balance of strength, durability, and weight. The most popular aluminum alloy used is 7075-T6, which provides excellent strength and resistance to corrosion.
Polymer:
Polymer lower receivers are gaining popularity due to their lightweight nature and ease of customization. These receivers are often made from high-strength polymers like reinforced nylon or polyphenylene sulfide (PPS). Polymer receivers can be more susceptible to wear and tear, but they offer a significant weight savings over aluminum receivers.
Features and Customization
The AR-15 lower receiver features several key components and customization options:
Fire Control Group:
The fire control group includes the trigger, hammer, and safety selector. These components are responsible for the firearm’s operation and can be swapped out for different trigger types and safety selectors to suit your preferences.
Magazine Well:
The magazine well is designed to accept various types of magazines, allowing for quick and easy reloading. Some lower receivers come with magazine wells that can be customized to fit specific magazine types or to enhance magazine release functionality.
Mounting Points:
The lower receiver features several mounting points for accessories, such as optics, sights, and grips. These mounting points are typically M-LOK or Picatinny rails, which provide a wide range of compatibility with various accessories.
Legal Considerations
It’s important to be aware of the legal aspects surrounding the AR-15 lower receiver. In the United States, the lower receiver is considered the firearm’s “frame,” and its sale and ownership are subject to federal and state regulations.
Background Checks:
Under federal law, the sale of a lower receiver requires a background check through a licensed firearms dealer. This ensures that the buyer is legally eligible to own a firearm.
Registration:
In some states, lower receivers may be subject to registration or reporting requirements. It’s essential to research and comply with the specific regulations in your area.
Conclusion
The AR-15 lower receiver is a vital component of the AR-15 rifle, offering a foundation for customization and performance. By understanding the dimensions, materials, features, and legal aspects of the lower receiver, you can make informed decisions when selecting and owning an AR-15 rifle.
