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Which AR-15 Parts Fail First?

Which AR-15 Parts Fail First?

March 06, 2019

You’re at the range. It’s you, your AR, and a whole lot of paper targets. You’re nailing bullseyes left and right, rehearsing drills like they are second nature. You’re thrilled with the performance of your AR, thinking, "This might be my best range day ever." Until it suddenly isn’t.

Your rifle jams. Your safety lever catches. The forward assist isn’t assisting anyone anymore. A magazine tumbles out of the well. What went wrong?

Even the best-made ARs eventually wear out and need repairs. But your rifle doesn’t wear evenly, and some parts take more abuse than others. In these cases, it’s best to have some spare parts on hand for your next range trip or to do regular preventative maintenance to prevent the issue entirely. But which parts wear out first?


The What and Why of Wear

Thanks to modern firearm design and manufacturing tolerances, it’s rare that most shooters will ever wear out their firearms. But for those who make a trip to the range a regular ritual or take part in shooting competitions and challenges, they’re putting a lot of stress on their rifle.

Most parts and components of your rifle have what’s generally referred to as "wear durability." This basically means how quickly a part or component wears out with use. Most leading AR parts and accessories brands produce products with a high level of wear durability. But any time you use a part, you wear it out a little bit more. This accumulated wear can result in a slew of issues, like loose parts, decreased accuracy, jams, and misfeeds.

When we think of wear on a part, we think of things like the infamous "idiot scratch" on the side of a 1911 pistol, or a shot-out barrel. But in reality, much of the wear we put on our rifle is hard to see or is on parts that we rarely think about, let alone check. That’s why it’s important to be aware of these parts and have replacements on hand. Let’s explore some of the parts that are likely to wear out on your AR-15 first.

Gas Tube Components

Your gas tube is one of the hardest working parts on your AR. Within it are a series of parts and careful design elements that make it effective and reliable.

For instance, the gas tube itself has a flared end which helps to create a positive seal between the tube and the gas key. Over time, that slight flare wears away and flattens. Eventually, this creates a negative seal which allows gases to escape. This leads to a slew of cycling issues that can be frustrating to deal with.

Within the gas tube are roll pins that keep the gas tube and gas block together. While it’s rare for these to fall out on their own, it does happen on occasion, necessitating a quick replacement for your rifle to continue to cycle properly.

The Bolt

The bolt of your AR was designed to be used and abused, but if you’re really working your rifle hard, the bolt might be one of the first parts to give up the ghost. Bolt failures typically occur in one of two places. The body of the bolt itself could fracture near the cam pin hole. Sometimes, this fracture will be one side only, but the fractures can spread to both sides of the bolt, effectively splitting the bolt in two.

The other way your bolt can break is along the locking lugs. Unfortunately, locking lugs are hard to identify unless they’ve broken free of the bolt and have collected in the chamber, causing a jam of some kind. It’s likely that you won’t notice a broken lug until you’re cleaning the AR. As such, you’ll want to take care inspecting your bolt carefully while cleaning your rifle.

Bolt Gas Rings

The gas rings on your AR bolt take nearly as much abuse as the bolt itself does. The combination of heat, pressure, and friction wears them down over time. With enough use, these rings can fail, allowing more gas to be released and prevents the bolt carrier group from cycling properly.

To check for worn or failing gas rings, try this simple process. Pull the bolt fully forward from the carrier and set the carrier on a flat surface with the bolt facing down. If the carrier’s weight can force it to fall down on top of the bolt, then it’s a sign that you need to replace your gas rings. Fortunately, gas rings are very affordable, and can easily be replaced with some patience and some fine tools like a dental pick. Just make sure that your gas rings are offset from one another when you replace them.

The Firing Pin

If you haven’t picked up on it yet, by now you should realize that many of the minute and precise pieces within your bolt carrier group are prone to wearing out faster than other parts. That includes, of course, your firing pin.

On rare occasions, the tip of your firing pin can fracture and break. However, more commonly, the tip of your firing pin will simply become misshapen with time and use. The tip can become jagged, blunted, or even dented. All of these deformations can impact the pins ability to strike the primer of your next round properly. If your firing pin appears damaged in any way, it’s best to just replace the part entirely.


For most firearms, the extractors are one of the most common places of wear and tear. For AR-15s, however, the extractor is particularly prone to damage and wear. They can crack, chip, or break entirely depending on what kind of ammo casing you’re shooting. Steel cased ammo can accelerate the degradation of your AR extractor dramatically. The extractor can wear away, essentially making it impossible for it to grab on to the rim of the casing and eject the spent round.

In addition to the extractor itself are the supporting parts. The springs and buffers of the extractor should be replaced regularly. If these components appear to be smashed or permanently compressed, replace them immediately.

For Parts That Won’t Fail, Choose Rail Scales

Whether you shoot casually on the weekends or you’re at the range every day, you don’t want to sacrifice on the quality of parts you’re putting on your AR. That’s why RailScales uses premium quality materials to construct all of our handgrips, iron sights, and rail covers. Order your premium AR parts and accessories from RailScales. today.