Centurion Arms CM4 5.56 Forged AR-15 Lower Receiver
Click to see full view
Plan where it ships
Firearms ship to a dealer (FFL), not your door. Pick one now to see your full cost.
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
Available Merchants(1)
Prices checked
Stock Alert
October 2026 on GunPartPicker
Centurion Arms CM4 5.56 Forged AR-15 Lower Receiver ranked #208 of the 588 lower receivers builders added on GunPartPicker in October 2026. Builders have added it to their builds on GunPartPicker. Since April 2026, it ranks #83 of the 1,217 lower receivers builders have added. Builds with this lower receiver are mostly chambered in 5.56 NATO (91%), split between mid-length (44%) and carbine-length (39%) gas systems, and nearly all AR-15.
Availability is good: it was in stock at one retailer or another nearly every time we checked in October 2026, but today the one retailer we track is out of stock. Prices barely moved in October 2026, holding around $128.25, with no real sale all month. Listed prices start at $128.25 at Primary Arms for when it comes back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
Not sure which lower receiver to pick?
We ranked every lower receiver by how often it shows up in real builds on GunPartPicker.
Read the guide: AR-15 Lower Receiver Trends →Check it against the live catalog:
Frequently Built With
The part most often added in each category by the builds that include this one
B5 Systems Type 22 P-Grip - Black
Bravo Company Mfg Upper Receiver Assembly w/ Laser T-Markings, Hard Coated Anodized - 4-UR-M4
B5 Systems Government Issue SOPMOD Stock Collapsible Mil-Spec Black
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
CaliberBased on real build data showing which calibers builders choose alongside this product.
Gas SystemBased on real build data showing which gas system lengths builders use with this product.
Builds Featuring This Part
See all builds →Builds in the community that include the Centurion Arms Cm4 5.56 Forged Ar-15 Lower Receiver
| Build | Parts | Total |
|---|---|---|
 | 9 | $1197.66 |
No reviews yet. Be the first to review this product!