5.7x28mm Complete Upper 16" - AR57
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AR57
Overview
The AR57 5.7x28mm Complete Upper features a 16" barrel, making it a ready-to-install option for builders looking to chamber their AR-15 in the unique 5.7x28mm round. This complete upper assembly simplifies the building process, allowing for a straightforward swap on your existing lower receiver while delivering the performance characteristics associated with this caliber. It's commonly found in builds aimed at versatility and a lighter shooting experience.
Specifications
September 2026 on GunPartPicker
AR57 5.7x28mm Complete Upper 16" - AR57 ranked #267 of the 615 upper receivers builders added on GunPartPicker in September 2026. Builders on GunPartPicker first added it to a build in August 2026.
It was hard to find in September 2026, in stock on only 4 of the 24 days we checked, and today only Classic Firearms has it in stock. Prices barely moved in September 2026, holding around $679.99, so there haven't been real sales lately. Buying today, the lowest price is $679.99 at Classic Firearms, which matches the best price we saw in September.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 35 retailers
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