Stag Arms AR-15 A3 Upper Receiver Assembly 5.56mm Left Hand
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Stag Arms
Overview
The Stag Arms AR-15 A3 Upper Receiver Assembly is a complete upper designed for the AR-15 platform, chambered in .223 Wylde, which allows for optimal versatility with both .223 Remington and 5.56 NATO ammunition. The A3 receiver type features a flat top rail, providing a solid foundation for optics and accessories, while the mid-length gas system enhances reliability and reduces felt recoil during operation. This upper is commonly found in builds that prioritize a balanced shooting experience and versatility for various applications.
Specifications
Stag Arms AR-15 A3 Upper Receiver Assembly 5.56mm Left Hand
Available Merchants(3)
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Build history on GunPartPicker
Builders have been adding the Stag Arms AR-15 A3 Upper Receiver Assembly 5.56mm Left Hand to their builds on GunPartPicker since February 2026. All time, it ranks #916 of the 1,652 upper receivers builders have added. Builds with this upper receiver are nearly all chambered in .223 Wylde, nearly all on mid-length gas, and nearly all AR-15.
It was out of stock everywhere we track for all of September 2026, and today none of the 3 retailers we track has it in stock right now.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 35 retailers
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Frequently Built With
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Builds Featuring This Part
See all 2 →Builds in the community that include the Stag Arms Ar-15 A3 Upper Receiver Assembly 5.56mm Left Hand
| Build | Parts | Total |
|---|---|---|
 | 27 | $2163.73 |
 | 24 | $2725.44 |
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