Centurion Arms CM4 5.56 Forged AR-15 Lower Receiver
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This is a serialized firearm.
Centurion Arms
Overview
The Centurion Arms CM4 5.56 Forged AR-15 Lower Receiver is a stripped lower designed to provide a solid foundation for your build. Made from billet aluminum and finished with hardcoat anodizing, this lower is built to withstand the rigors of use while maintaining a lightweight profile. With a trigger pin diameter of .154, it is compatible with a wide range of triggers, making it versatile for different configurations. This lower commonly appears in builds utilizing an intermediate gas system and chambered in 5.56 NATO.
Specifications
August 2026 on GunPartPicker
Centurion Arms CM4 5.56 Forged AR-15 Lower Receiver ranked #80 of the 507 lower receivers builders added on GunPartPicker in August 2026. Builders have been adding it to their builds on GunPartPicker since March 2026. All time, it ranks #55 of the 983 lower receivers builders have added. Builds with this lower receiver are nearly all chambered in 5.56 NATO, mostly on mid-length gas (67%, then rifle-length 33%), and nearly all AR-15.
It was in stock most days in August 2026, and today the one retailer we track has it in stock. Prices barely moved in August 2026, holding around $128.25, so there haven't been real sales lately. Buying today, the lowest price is $128.25 at Primary Arms, which matches the best price we saw in August.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 31 retailers
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Frequently Built With
The part most often added in each category by the 34 builds that include this one
B5 Systems Type 22 P-Grip - Black
B5 Systems Government Issue SOPMOD Stock Collapsible Mil-Spec Black
Bravo Company Mfg Upper Receiver Assembly w/ Laser T-Markings, Hard Coated Anodized - 4-UR-M4
Geissele Automatics Super Semi-Automatic Enhanced SSA-E Two Stage AR-15 Trigger .154"
Bravo Company M16 Bolt Carrier Group Black
B5 Systems Trigger Guard ATG-001-01
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 1 →Builds in the community that include the Centurion Arms Cm4 5.56 Forged Ar-15 Lower Receiver
| Build | Parts | Total |
|---|---|---|
 | 9 | $1195.14 |
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