Daniel Defense MK18 RIII, 5.56mm, 10.3 Barrel, Black, Upper Receiver Group
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Daniel Defense
Overview
The Daniel Defense Mk18 RIII Upper Receiver Group is a stripped assembly designed for the AR-15 platform, featuring a 10.3-inch barrel optimized for 5.56 NATO ammunition. This upper receiver is crafted from 7075-T6 aluminum, ensuring a lightweight yet robust construction, making it suitable for various applications. Commonly found in builds utilizing a carbine gas system, this upper is ideal for those looking to create compact, maneuverable firearms.
Specifications
Daniel Defense MK18 RIII, 5.56mm, 10.3 Barrel, Black, Upper Receiver Group
August 2026 on GunPartPicker
Daniel Defense MK18 RIII, 5.56mm, 10.3 Barrel, Black, Upper Receiver Group ranked #168 of the 690 upper receivers builders added on GunPartPicker in August 2026. Builders have been adding it to their builds on GunPartPicker since February 2026. All time, it ranks #138 of the 1,636 upper receivers builders have added. Builds with this upper receiver are nearly all chambered in 5.56 NATO and nearly all AR-15.
It was in stock most days in August 2026, and today all 5 retailers we track have it in stock. Prices barely moved in August 2026, holding around $1,470.85, so there haven't been real sales lately. Buying today, the lowest price is $1,454 at Primary Arms, which matches the best price we saw in August.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 35 retailers
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Frequently Built With
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Geissele Super Charging Handle (SCH), 7.62, Desert Dirt Color 05-476S
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Builds Featuring This Part
See all 2 →Builds in the community that include the Daniel Defense Mk18 RIII, 5.56mm, 10.3 Barrel, Black, Upper Receiver Group
| Build | Parts | Total |
|---|---|---|
 | 14 | $3783.52 |
 | 36 | $21843.42 |
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