Given the popularity of the AR-15 and AR-10 rifles, there are a lot of questions people have regarding which parts are interchangeable between the two platforms. While these rifles do look similar, they are also different in many important ways.
Many people think the term AR stands for “assault rifle” or “automatic rifle”, but it’s an abbreviation for “Armalite Rifle”. This is a manufacturer that originally developed the AR rifle. The AR-10 is a model created by Armalite. Today, the term AR-10 most often refers to AR-15 style rifles that are chambered in .308 caliber.
The two most popular AR-10 specifications that are used today are the Armalite style and DPMS style. We will list the compatibility of both styles below.
Differences between the AR-15 and AR-10
The first and most important difference between the AR-15 and AR-10 is the caliber. AR-10 rifles use .308 or 7.62x51mm rounds, whereas AR-15 rifles are chambered for .223 or 5.56x45mm rounds. This means some of the parts in the AR-10 platform must be larger to account for the larger ammunition. This also causes a difference in weight between the two rifles.
AR-15 and AR-10 Compatibility List
| AR-15 Lower Receiver Parts (Mil-Spec) | DPMS .308 | Armalite .308 |
| Lower Receiver | NO | NO |
| Stock | YES | YES |
| Castle Nut | YES | YES |
| Receiver End Plate | YES | YES |
| Buffer | NO | NO |
| Buffer Retainer | YES | YES |
| Buffer Spring | YES | YES |
| Trigger Guard | YES | YES |
| Safety Selector Assembly | YES | YES |
| Takedown Pin Assembly | NO | NO |
| Pivot Pin Assembly | NO | NO |
| Pistol Grip | YES | YES |
| Magazine | NO | NO |
| Magazine Catch | YES | NO |
| Magazine Release Button & Spring | YES | YES |
| Bolt Catch | NO | NO |
| Bolt Catch Roll Pin | NO | YES |
| Bolt Catch Spring & Plunger | YES | YES |
| Trigger | YES | YES |
| Hammer | YES | YES |
| Trigger & Hammer Springs & Pins | YES | YES |
| Disconnect | YES | YES |
| AR-15 Upper Receiver Parts (Mil-Spec) | DPMS .308 | Armalite .308 |
| Upper Receiver | NO | NO |
| Bolt Carrier | NO | NO |
| Bolt Assembly | NO | NO |
| Muzzle Device | NO | NO |
| Gas Block | YES | YES |
| Gas Tube | YES | YES |
| Handguard | NO | NO |
| Barrel | NO | NO |
| Barrel Nut | NO | NO |
| Forward Assist | YES | YES |
| Ejection Port (Dust Cover) | NO | NO |
| Charging Handle | NO | NO |
