AR-15 and AR-10 platforms: Compatibility and Differences

In this article, we will explore the main differences and compatibilities of AR-15 and AR-10 rifles, which of their parts are different and which are the same, and what you can buy for both rifles to save a buck.

First, a little history. The ArmaLite AR-10 is a 7.62×51mm NATO battle rifle designed by Eugene Stoner in the late 1950s and manufactured by ArmaLite. It failed completely. Armalite didn't win the military contract, but got the notes that they wanted a more compact version, Stoner went back to work with a redesign resulting in the AR15, chambered in 5.56mm NATO, being released the very next year. 

This setback caused the company to fold. In 1959, Colt Mfg. Co. bought out the patent and brought the platform into the limelight as AR15, started to mass producing the platform for the first time to support the Vietnam War efforts. DPMS came in later to create what is now known as LR10 or 308 platform, adapting the design of AR15 into a 308 version of it. Since both platforms were virtually born from each other, that means they have a lot in common.

AR-10 VS AR-15: INTERCHANGEABLE PARTS?

• Buttstock - Buttstock especially rifle size are very interchangeable with each other. However, thing to remember - not the buffer or buffer springs! Those are different for both.
• Buffer tube with castle nut and end plate
• Hammers
• Magazine release buttons
• Pistol grips
• Safety selector switch
• Trigger groups - Although the calibers differ from AR-15 (which is a 5.56 caliber) to AR-10 (which is a 7.62 caliber), you can use the same triggers. Although now days, more advance triggers are developed for 7.62x51. We offer few varieties for AR-10 triggers at Moriarti Armaments.
• Forward Assist
• Muzzle brake for 30 cal (usually 5/8x24 pitch)

Another thing that is compatible with AR-15 and AR-10 rifles are Bolt catch pins. 308AR AR-10 Bolt Catch Pin is a standard option that fits AR-10, AR-15 and 308AR, and is a perfect choice for replacing your old Bolt catch pin.

Here are the parts that are not interchangeable between the AR10 and Ar15:

• Barrels
• Bolt catch
• Take down pins
• Handguards and rail systems
• Dust cover
• Upper Receiver
• Charging Handle

So which one to get? Ar-15 or AR-10?

The answer depends on you. We will advocate to start with AR-15 build kit as its more economical, easier to use, can be applied for home defense, and is more versatile. However, our answer will be guided by your ‘intended use.’ If you need help finding your answer, reach out to our legendary customer service team to walk you through the process of building your own  AR-15 or AR-10 rifle.