ProMag DPMA4 40-Round .308 Winchester AR-10 Magazine - Black Polymer

The ProMag DPMA4 delivers extended capacity for AR-10 platform rifles chambered in .308 Winchester, providing 40 rounds of reliable feeding in a lightweight polymer construction. Built from DuPont Zytel polymer, this magazine offers shooters increased firepower without the weight penalty of steel alternatives.

What Makes This Different

Unlike standard 20-round AR-10 magazines, the DPMA4 doubles capacity while maintaining compatibility with DPMS-pattern lower receivers. The DuPont Zytel polymer construction reduces weight by approximately 30% compared to steel magazines of similar capacity. Heat-treated steel springs and anti-tilt followers ensure consistent feeding under rapid fire conditions.

Key Features

• 40-round capacity for .308 Winchester/7.62x51 NATO cartridges
• DuPont Zytel polymer body resists impact and chemical damage
• Compatible with DPMS-pattern AR-10 rifles and variants
• Heat-treated steel spring maintains tension over extended use
• Anti-tilt follower prevents feeding malfunctions
• Textured grip surfaces for secure handling during reloads
• Drop-free design enables rapid magazine changes

Field testing demonstrates reliable cycling through various .308 Winchester loads, from 147-grain FMJ to 175-grain match ammunition. The extended capacity proves advantageous in competitive shooting disciplines, tactical training scenarios, and hunting situations requiring multiple follow-up shots. Temperature extremes from -20°F to 140°F show minimal impact on feeding reliability.

Technical Specs

• Capacity: 40 rounds
• Caliber: .308 Winchester/7.62x51 NATO
• Material: DuPont Zytel polymer body with steel internals
• Compatibility: DPMS-pattern AR-10 rifles
• Weight: Approximately 8.5 ounces empty
• Overall length: 12.5 inches
• Finish: Matte black
• Country of origin: USA

The DPMA4 addresses the capacity limitations of standard AR-10 magazines without sacrificing reliability or adding excessive weight. ProMag's polymer construction and proven feeding geometry make this magazine a practical upgrade for shooters requiring extended capacity in .308 Winchester platforms.