Barnes Suppressor Series .300 AAC BLK 220gr Sierra MK Subsonic 20rd 32518

The Barnes Suppressor Series .300 AAC BLK 220gr Sierra MK is the definitive choice for shooters who demand match-grade precision without the "sonic crack." While many subsonic rounds struggle with "short-stroking" and inconsistent cycling, this load is purpose-built to run flawlessly. Optimized specifically for suppressed AR-15 platforms, it delivers the legendary accuracy of a Sierra MatchKing with a whisper-quiet signature, making it the premier choice for tactical training and long-range subsonic competition.

The primary failure of heavy subsonic .300 Blackout ammo is unreliable gas system performance. Barnes solves this by pairing the iconic 220-grain Sierra MatchKing (SMK) with a custom-tuned propellant burn curve. Unlike standard lead-nose subsonics that can be erratic, the MatchKing’s high ballistic coefficient (G1: 0.608) ensures predictable flight and tighter groups. You get consistent bolt velocity for reliable semi-auto cycling and repeatable point-of-impact, even at the outer limits of subsonic range.

Success at the range is measured by stability and reliability. Traveling at 1,040 fps, this 220-grain heavy hitter eliminates the "sonic crack" while maintaining enough momentum to keep your trajectory flat and predictable. Built with premium reloadable brass and consistent Boxer primers, this load ensures reliable ignition and smooth cycling under sustained fire. It’s a controlled, match-grade shot that bridges the gap between suppressed discretion and world-class accuracy.

Features

• 220-Grain Sierra MatchKing (OTM): The gold standard for precision, utilizing an Open Tip Match design for sub-MOA accuracy and extreme consistency.
• Optimized .300 AAC BLK Powder Curve: Custom-tuned propellant ensures reliable semi-auto cycling while reducing gas blowback and suppressor fouling.
• High G1 Ballistic Coefficient (0.608): Superior aerodynamic stability reduces vertical dispersion for repeatable precision at subsonic distances.
• Subsonic 1,040 fps Velocity: Purpose-built to stay below the speed of sound, providing a true low-signature shooting experience without the sonic crack.

Technical Specifications

• Ballistics: .300 AAC Blackout | 1,040 fps (Subsonic) | 528 ft-lbs (Muzzle)
• Projectile: 220 Grain | Sierra MatchKing (OTM) | Jacketed Lead Core
• Cycling: Brass Case | Boxer Primed | AR-15 / Semi-Auto & Bolt-Action
• Logistics: 20 Rounds per Box | Commercial Cardboard | Suppressor Series Optimized
• Dimensions: 5.9" x 2.8" x 1.4" (~23.1 cu. in.) | Approx. 0.82 lbs | 32518
• Application: Suppressed Target Shooting | Match/Competition | Tactical Training
• Country of Origin: USA

When suppressed performance and precision matter, this is the load that removes variability from your system. Get consistent subsonic cycling and repeatable accuracy by sourcing from SMKW, a trusted supplier for duty-grade ammunition and technical reliability.