Rifle Receivers

A rifle receiver is the serialized, regulated component of a firearm — the part that is legally the “gun” under federal law and requires an FFL transfer. Impact Guns carries stripped lower receivers, complete lower receivers, and receiver sets for AR-15, AR-10, and other rifle platforms, making it straightforward to start or complete a build with a receiver that ships to your local FFL dealer.

Read our full Rifle Receivers Buying Guide ↓

Stripped vs. Complete Lower Receivers

A stripped lower receiver is the bare serialized housing with no internal components — it requires a lower parts kit (LPK) and stock assembly to function. A complete lower receiver ships fully assembled with the trigger group, safety selector, bolt catch, magazine release, pistol grip, and stock already installed. Complete lowers are ready to drop an upper onto; stripped lowers give you full control over every component. Most builders on a budget start with a stripped lower and an LPK; builders who want a specific trigger or stock combination also start stripped.

AR-15 Lower Receivers: What to Look For

AR-15 lower receivers are mil-spec or commercial spec — the difference is the diameter of the buffer tube threads. Mil-spec is the standard and is compatible with the widest range of stocks and components. All lower receivers sold as “AR-15” use the same external dimensions and accept standard upper receivers regardless of manufacturer. Material is typically forged 7075-T6 aluminum (most durable) or billet 7075-T6 (precision-machined, slightly heavier). Brands like Aero Precision are popular for quality-to-price ratio.

AR-10 and .308 Receivers

AR-10 and .308/7.62 NATO platform receivers are larger than AR-15 receivers and are not cross-compatible. There are two dominant pattern standards: DPMS (the most common) and Armalite (the original). DPMS-pattern uppers and lowers from different manufacturers are generally interchangeable; Armalite-pattern components are not compatible with DPMS. Always confirm pattern compatibility when mixing upper and lower from different manufacturers. See our AR-10 rifles and AR-10 parts for complete builds and components.

AK Receivers

AK-pattern receivers are milled or stamped steel — milled receivers are machined from solid steel and are heavier but extremely durable; stamped receivers are the original AK design, lighter and the standard for most production AKs. AK receivers are more complex to build from stripped than AR-15 lowers, typically requiring a hydraulic press and specific tools. Most civilian AK builds start with a semi-complete or complete lower. Zastava and Century Arms are common sources for AK-pattern complete rifles and parts.

Receiver Transfers: How It Works

Any serialized receiver — whether stripped or complete — must transfer through a licensed FFL dealer. When you order a receiver from Impact Guns, it ships to an FFL dealer near you for the standard transfer process: background check (NICS), 4473 form, and local transfer fee. Use our FFL dealer lookup to find a dealer near you before ordering. Receivers are subject to the same transfer requirements as complete firearms.

Frequently Asked Questions

Is a stripped lower receiver considered a firearm?
Yes. Under federal law, the serialized lower receiver is legally the firearm regardless of whether it has any other components attached. It requires an FFL transfer and background check to purchase, the same as a complete rifle. This applies to AR-15, AR-10, and all other serialized receivers.

Can I buy a lower receiver directly online without an FFL?
No. All serialized receivers must transfer through a licensed FFL dealer. Impact Guns ships receivers to an FFL dealer of your choice; you complete the transfer paperwork and background check at that dealer. Use our FFL dealer lookup to find a dealer near you.

What is the difference between mil-spec and commercial spec AR-15 lowers?
The difference is the diameter of the buffer tube (castle nut) threads. Mil-spec tubes measure approximately 1.148” in diameter; commercial-spec tubes measure approximately 1.17”. The two are not interchangeable — a mil-spec stock will not fit a commercial buffer tube and vice versa. The vast majority of quality AR-15 lowers use mil-spec dimensions. Always verify spec before ordering replacement stocks or buffer tubes.