KCI USA AR-15 Magazine 21rd 223/5.56 Translucent Smoke Polymer

The KCI USA KCIMZ066 magazine delivers reliable feeding for AR-15 platforms with its 21-round capacity in translucent smoke polycarbonate construction. This extended capacity magazine provides additional firepower while maintaining the lightweight characteristics shooters demand for competition and tactical applications.

What Makes This Different

Unlike standard 30-round magazines, this 21-round configuration offers an optimal balance between capacity and maneuverability. The translucent smoke material allows for quick visual ammunition counts without removing the magazine from the firearm. The polycarbonate construction resists impact damage while weighing significantly less than steel alternatives, reducing overall rifle weight during extended use.

Key Features

• 21-round capacity for 223 Remington and 5.56x45mm NATO cartridges
• Translucent smoke polycarbonate body for visual round counting
• Standard STANAG magazine profile fits all AR-15 pattern rifles
• Anti-tilt follower design prevents feeding malfunctions
• Reinforced feed lips resist deformation under pressure
• Removable floor plate for easy cleaning and maintenance
• Corrosion-resistant steel spring rated for extended use

Field testing demonstrates consistent feeding across various ammunition weights from 55-grain to 77-grain bullets. The magazine functions reliably in both semi-automatic and select-fire applications, making it suitable for law enforcement, competitive shooting, and recreational use. The polycarbonate material maintains flexibility in temperature extremes from -20°F to 140°F without becoming brittle or losing dimensional stability.

Technical Specs

• Capacity: 21 rounds
• Caliber: 223 Remington/5.56x45mm NATO
• Material: Translucent smoke polycarbonate body
• Compatibility: AR-15, M16, and STANAG pattern rifles
• Overall length: Approximately 7.5 inches
• Weight: 4.2 ounces empty
• Spring: Heat-treated steel with anti-corrosion coating
• Country of origin: USA

This magazine represents solid engineering focused on function over flashy features. The 21-round capacity strikes an ideal balance for shooters who need more than a 10-round magazine but don't require a full 30-round configuration. Quality construction and proven reliability make this a practical choice for serious shooters.