MK109 Mod 2-M 300 AAC Blackout Complete Upper Receiver - MK109 Mod 2-M 300 AAC Blackout 9.75" Bbl Complete Upper
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Primary Weapon Systems
Overview
The Mk109 Mod 2-M Complete Upper Receiver is designed specifically for the AR-15 platform and features a 9.75-inch barrel chambered in .300 Blackout. This upper utilizes a pistol-length gas system, which is critical for optimizing performance with subsonic and supersonic ammunition alike, ensuring reliable cycling and reduced recoil. This upper receiver is often found in builds focused on compact versatility and suppressed shooting capabilities, making it a solid choice for those looking to enhance their tactical setups.
Specifications
MK109 Mod 2-M 300 AAC Blackout Complete Upper Receiver - MK109 Mod 2-M 300 AAC Blackout 9.75" Bbl Complete Upper
Available Merchants(4)
Prices checked
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Build history on GunPartPicker
Builders on GunPartPicker first added the Primary Weapon Systems MK109 Mod 2-M 300 AAC Blackout Complete Upper Receiver - MK109 Mod 2-M 300 AAC Blackout 9.75" Bbl Complete Upper to a build in February 2026.
It was hard to find in September 2026, in stock on only 8 of the 20 days we checked, and today none of the 4 retailers we track has it in stock right now. It dipped to $1,299.95 at BattleHawk Armory for a stretch in September 2026, under its usual $1,399.95, so sales do come around. Listed prices start at $1,299.95 at BattleHawk Armory for when it comes back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
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