AR-15 MK1 Mod 1-M Upper Receiver Assembly 223 Wylde M-LOK - MK114 Mod 1-M Upper Receiver 14.5 Barrel .223 Wylde
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Primary Weapon Systems
Overview
The AR-15 Mk1 Mod 1-M Upper Receiver Assembly from Primary Weapon Systems features a complete design that includes a 14.5-inch barrel chambered in .223 Wylde, allowing for versatility with both .223 Remington and 5.56 NATO ammunition. This upper receiver is tailored for AR-15 platform builders looking to enhance their rifle’s performance while maintaining a compact profile. It is commonly found in lightweight builds intended for tactical applications and home defense.
Specifications
AR-15 MK1 Mod 1-M Upper Receiver Assembly 223 Wylde M-LOK - MK114 Mod 1-M Upper Receiver 14.5 Barrel .223 Wylde
Available Merchants(1)
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Stock Alert
Price and stock
The Primary Weapon Systems AR-15 MK1 Mod 1-M Upper Receiver Assembly 223 Wylde M-LOK - MK114 Mod 1-M Upper Receiver 14.5 Barrel .223 Wylde was out of stock everywhere we track for all of September 2026, and today the one retailer we track is out of stock. Listed prices start at $999.95 at Brownells for when it comes back.
Prices checked · refreshed daily across 37 retailers
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