Fortis Billet M4 Upper Stripped for AR15 223 Rem, 556 NATO - UBilletM4
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Fortis Manufacturing
Overview
The Fortis Billet M4 Upper Stripped receiver is designed for the AR-15 platform and is crafted from billet aluminum, providing a robust and precise foundation for your build. This upper is chambered in .223 Wylde, allowing for optimal versatility between .223 Remington and 5.56 NATO cartridges. It’s commonly used in builds that feature a mid-length gas system, making it a solid choice for those looking to balance performance and reliability in their rifle setup.
Specifications
Fortis Billet M4 Upper Stripped for AR15 223 Rem, 556 NATO - UBilletM4
September 2026 on GunPartPicker
Fortis Billet M4 Upper Stripped for AR15 223 Rem, 556 NATO - UBilletM4 ranked #267 of the 615 upper receivers builders added on GunPartPicker in September 2026. Builders have been adding it to their builds on GunPartPicker since February 2026. All time, it ranks #102 of the 1,642 upper receivers builders have added. Builds with this upper receiver are nearly all chambered in .223 Wylde, mostly on pistol-length gas (67%, then mid-length 33%), and nearly all AR-15.
It was hard to find in September 2026, in stock on only 15 of the 30 days we checked, and today 4 of the 5 retailers we track have it in stock. It dipped to $180.46 at Optics Planet for a stretch in September 2026, under its usual $189.95, so sales do come around. Buying today, the lowest price is $189.95 at Optics Planet, above September's low of $180.46, so a better deal may come back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 35 retailers
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Frequently Built With
The part most often added in each category by the 17 builds that include this one
ODIN Works O2 Lite M-LOK Free Float AR-15 Handguard - 7.5"
Fortis Manufacturing License Gen 2 AR-15 Stripped Lower Receiver Black
FAXON Firearms Suppressor Optimized Barrel 300BLK 7.5" Pistol Length Black
Radian Raptor Charging Handle & Talon Safety Selector Combo - OD Green
Fail Zero 6.5 Grendel Type II AR-15 Bolt Carrier Group - No Hammer
WMD Guns AR-15 Gas Tube Nitromet Mid-Length
Build Configuration Breakdown
Aggregated and anonymized data showing how builders use this product
Gas SystemBased on real build data showing which gas system lengths builders use with this product.
Builds Featuring This Part
See all 3 →Builds in the community that include the Fortis Billet M4 Upper Stripped for AR15 223 Rem, 556 NATO - UBilletM4
| Build | Parts | Total |
|---|---|---|
 | 14 | $2097.07 |
 | 22 | $1959.61 |
 | 16 | $1644.04 |
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