If you’re a fan of the AR-15—or just curious about it—you might have noticed a few things about the platform. Factory guns and components are marketed with labels like Mil-Spec, free-floated, M-LOK compatibility, and so on. You’ve likely also seen “forged” and “billet” used to describe an AR-15 (or AR-10) receiver, and that’s what we’re going to cover today. The receivers on your gun might be forged or billet, which have some significant differences. Which one’s better? Does it even matter? We will attempt to answer those questions and explain a few things along the way.
What’s an AR-15 receiver?
Before we get into the debate of forged vs. billet, let’s pause and cover receivers. The AR-15 platform has two receivers—the lower receiver and the upper receiver. The lower is, as its name suggests, the part that’s located on the lower half of the gun, and it contains important parts, like the trigger and safety selector. As for the upper, it’s a smaller part that connects on top of the lower receiver by using a pair of thick ‘takedown’ pins. The barrel and handguard attach to the upper receiver, and the BCG (bolt carrier group) is contained in the back of the upper. The receiver set is the main body of the AR-15 and holds everything together. Receivers can be forged or billet and are generally the serialized part of the gun.
What’s a forged AR-15 receiver?
At its simplest, a forged receiver is a block of metal. High-quality aluminum is typically used, and the block of material is then pounded into the desired shape using mechanical force (so no, there’s not a blacksmith beating metal into submission by hand). It takes an enormous amount of force to forge a receiver from a block of metal.
Although not always, 7075-T6 aluminum is the most commonly used metal in lower receivers. This metal’s ultimate tensile strength falls between 74,000 psi and 78,000 psi. When forged, the molecules are more tightly compressed, which increases strength and maximizes wear resistance. A forged lower receiver is often lighter weight than a billet receiver, and it’s usually more affordably priced as well.
What’s a billet AR-15 receiver?
A billet AR-15 receiver is one that’s created by directly cutting the metal. CNC machines are used in this process for optimal precision. After all, an AR lower receiver has specific tolerances and requirements to correctly house moving parts and ensure proper function when in use. Just how tightly those tolerances are adhered to depends on the manufacturer, but these parts are normally machined to millionths of an inch, so you can imagine how precise their construction is.
The end weight of a billet receiver depends on the design and how much metal is left in place. A simple design could make it lighter than a forged receiver, but once things get more elaborate, weight tends to increase. Billet receivers do demonstrate excellent tensile strength and deliver superior fitment compared to most forged receivers.
Forged vs. billet—which one’s better?
There are drawbacks to both forged and billet receivers. First, check out the drawbacks of forged receivers:
- Tolerances tend not to be as exact
- More prone to aesthetic blemishes and imperfections
- Less-than-ideal fitment when joining upper and lower receivers
- Not many options for unique or interesting designs
- Might be more likely to crack or have failure points within the metal
Drawbacks to billet receivers:
- Greater cost
- Higher weight due to more metal being left in place
- Generally not as strong as forged receivers, although it would take tremendous crushing force to damage it
- Billet receivers might not be as broadly compatible and may need to be paired in a matched set
When you’re choosing a billet or forged receiver, the choice is ultimately yours. Both types of receivers are capable of withstanding hard use. The actual quality and fitment depend on the manufacturer. Metallurgists agree that the typical forged receiver is a bit stronger than a billet receiver. But also point out that the difference isn’t enormous. If you want a lower receiver that’s compatible with most parts on the market, you’re probably going to go with a forged model (that or a simple billet design). And if you’re trying to get a more budget-friendly gun, forged is usually the way to go.
However, if you want a sharp, custom aesthetic or require the greatest possible fitment, billet receivers are likely to be what you need. Although they cost more, billet receivers are the best way to get a unique-looking gun with the stellar fitment of parts.
Should you get a billet or forged receiver?
There is indeed no “right” choice, and the differences between billet and forged are relatively minor. In my experience, both types of receivers work well. Frankly, the only receiver I’ve ever destroyed to the point of not working was likely a fluke (and it was forged, which is generally supposed to be stronger).
In most cases, the fitment of forged receiver sets is fine, although you’re a lot more likely to have slight gaps or wiggles. That bothers me about precision rifles or anything I’m depending on for precision or long-range shooting. For those circumstances, I do have guns with billet receivers. On the other hand, I have a forged receiver AR-15 that’s reliably capable of sub-half MOA groups.
In the end, you really need to pay attention to the manufacturer and their own dedication to tolerances and quality. Just because a receiver is marked forged or billet doesn’t mean it’s guaranteed to be superior or inferior in some way. Do your homework. Find out which brands you can trust, and go from there. The great forged vs. billet debate will go on forever, and there is unlikely to ever be a real winner.
