Are AR-10 and AR-15 Parts Interchangeable?

When building or customizing an AR-style rifle, the question of parts compatibility often arises, especially when it comes to the AR-10 and AR-15 platforms. These two rifles, while similar in design and operation, are chambered for different calibers and have distinct specifications, leading many enthusiasts to wonder if their parts are interchangeable. Whether you're upgrading your current build or starting a new one, understanding the compatibility between AR-10 and AR-15 parts is essential to ensure a smooth, functional setup.

In this blog, we’ll break down the differences and similarities between the two rifles and provide a clear guide on which parts can and cannot be swapped between the AR-10 and AR-15 platforms. Let's dive in!

The Basics: AR-10 vs. AR-15

Before we delve into parts compatibility, it’s essential to understand the primary differences between the AR-10 and AR-15. While both rifles share the same core design, they are chambered for different calibers:

• AR-15: The AR-15 is typically chambered in .223 Remington or 5.56 NATO, which are lighter and smaller rounds designed for rapid fire, close to medium-range engagements, and general-purpose use. The AR-15 is popular for everything from home defense to varmint hunting, recreational shooting, and competitive events.

• AR-10: The AR-10, on the other hand, is chambered in larger, more powerful calibers like .308 Winchester, 7.62 NATO, and other similar cartridges. This gives the AR-10 greater range and stopping power, making it ideal for long-range precision shooting, hunting large game, and military applications.

Despite these differences, the two rifles share a similar design, which gives rise to the question of parts interchangeability.

What’s Common Between the AR-10 and AR-15?

The AR-10 and AR-15 share a similar operating system, gas impingement design, and modular construction, which allows for a degree of interchangeability. However, while many components are similar in function and design, the dimensions of key parts—particularly those related to the receiver and bolt carrier—differ significantly.

Parts That Are Not Interchangeable

Here’s a breakdown of the key parts that are not interchangeable between the AR-10 and AR-15:

1. Lower Receiver:

   • The lower receiver is one of the main differences between the AR-10 and AR-15. The AR-10 is a larger platform, requiring a wider and stronger lower receiver to handle the more powerful .308 and 7.62 NATO cartridges. The AR-15 lower receiver, being smaller, will not fit the AR-10’s parts. Furthermore, the pin sizes, magazine well, and trigger guard of the two rifles differ.

   • Takeaway: The AR-10 and AR-15 lower receivers are not interchangeable, even though both are technically "AR-style."

2. Bolt Carrier Group (BCG):

   • The bolt carrier group in the AR-10 is built to handle the larger, more powerful cartridges used by the AR-10. The dimensions of the bolt and carrier are significantly larger compared to the AR-15's BCG.

   • Takeaway: The AR-15 BCG will not fit into the AR-10, and vice versa.

3. Barrel:

   • The barrel of the AR-10 is significantly larger and more robust to handle the recoil and pressure from larger calibers like .308. AR-15 barrels, while similar in design, are smaller in diameter and designed for the lighter .223/5.56 rounds.

   • Takeaway: AR-15 barrels are not compatible with AR-10 rifles.

4. Buffer and Buffer Tube:

   • The buffer tube and buffer spring are also different between the two rifles. The AR-10 uses a heavier buffer system due to the increased recoil of the .308 cartridges, while the AR-15 has a lighter buffer.

   • Takeaway: The AR-15 buffer system will not work in the AR-10 and vice versa.

Parts That Are Interchangeable

While the AR-10 and AR-15 are different in some key areas, there are certain parts that can be interchangeable. These include:

1. Upper Receiver (with Caveats):

   • While the upper receivers of the AR-15 and AR-10 are different in terms of size, many manufacturers make "AR-15-compatible" AR-10 uppers. However, this is only true when the AR-10 is built using an AR-15-style design, such as those based on the DPMS Gen 1 or Gen 2 platform.

   • Takeaway: In some cases, the upper receiver can be swapped, but this depends on the specific model and design of both the AR-10 and AR-15.

2. Handguards and Rail Systems:

   • Handguards and rail systems for both AR-10 and AR-15 rifles can often be swapped if they are designed to fit the same barrel nut and attachment system. Many manufacturers offer universal designs that work across both platforms.

   • Takeaway: Some handguards and rail systems are interchangeable, particularly if they are designed with modularity in mind.

3. Triggers:

   • The trigger assembly is generally compatible between the AR-10 and AR-15 as long as both rifles are built around the same platform. For example, if you have an AR-10 based on the DPMS design, an AR-15 trigger that fits the same receiver design should work in both rifles.

   • Takeaway: Trigger assemblies are often interchangeable, but it's important to check compatibility based on the specific lower receiver design.

4. Stock Assembly:

   • The stock assembly (including the buttstock and buffer tube) can be interchangeable in some cases, but you will need to use the correct buffer system for your caliber. Many AR-15-style stocks will work on AR-10 lower receivers, provided the buffer and tube are compatible.

   • Takeaway: Stock assemblies can be swapped if you use the appropriate buffer system.

Conclusion:

While both the AR-10 and AR-15 share many similarities in their modular design and functionality, their differences—especially in terms of caliber and receiver size—mean that many parts are not interchangeable. The lower receivers, bolt carrier groups, barrels, and buffer systems are some of the major parts that differ between the two rifles. However, there are some parts, like certain upper receivers, handguards, triggers, and stocks, that can be swapped depending on the specific models and platform designs.

When building or upgrading your rifle, always check compatibility to ensure that the parts you're using are specifically designed to work with your chosen platform. At ShootersGate.com, we offer a wide range of AR-10 and AR-15 parts, ensuring that you get the right components for your build.

Need parts for your next build? Browse our selection of high-quality AR-10 and AR-15 components and find everything you need to customize your rifle to perfection!