If you’re somewhat new to the AR-15 platform you might find things that catch you by surprise. The proper use of gas operated weapons like the AR-15 is a bit more complicated than that of your average hunting rifle or handgun. You may have heard stories of AR-15 jamming, failure to feed, and short stroke and wonder what causes them. Maybe you need to know how to clear a double feed. Let's take a look at the common stoppages and malfunctions of the AR-15 and help you with some of those mysteries.
At one time, or another, it is likely that you will encounter a situation where your AR doesn't behave as you expect it to. You might squeeze the trigger and find it gives only a little and feels mushy or it might give a click while nothing else happens. Perhaps you’ve just fired one, or maybe several rounds, and now your weapon won’t fire again.
When one of these things occurs, what you’re experiencing is a stoppage of your AR system. Simply put, a stoppage is any situation where your AR-15 fails to complete a cycle of operation. Stoppages may be caused by simple human error or by mechanical malfunction. Many basic stoppage situations can be remedied immediately in the field and will not necessarily repeat themselves. If you have ever failed to chamber the first round and pulled the trigger with no results, you have experienced a stoppage caused by human error. Obviously this stoppage is a simple one to resolve, other stoppages may be more complicated and have mechanical roots. These are malfunctions of your AR system.
Immediate Action: “Tap, Rack, and Reassess”
The first attempt to remedy any stoppage of an AR-15 should be what those in the know call Immediate Action: “Tap, Rack, and Reassess.”
- “Tap” your magazine to be sure it is properly seated
- “Rack” pull the charging handle of your AR-15 back swiftly with ample force and release it cleanly
- “Reassess” This replaces the “Bang” part of the cycle many veterans were taught. Simply said, before firing, be sure that there is still a reason to do so and that it is still safe to fire. Once those conditions are established, feel free to give the “bang” portion a try.
The Tap, Rack, and Reassess cycle will resolve a great many AR-15 stoppages. In fact, the going estimate is that 90 to 95 percent of all stoppages can be resolved with a quick run through of this process. Most of the stoppages that are cleared in this manner would be considered type 1, simple stoppages that may not have a specific known source. If this doesn’t solve your problem, you may have a more complex stoppage such as the stovepipe jam.
The Stovepipe Jam
The stovepipe jam is simply diagnosed. The appearance of a stovepipe jam is the source of its moniker. When this particular type of jam occurs, a piece of spent ammunition, empty brass if you will, is caught in the ejection port, causing an obstruction to the chamber or feed-way. The brass was extracted properly, but did not eject and is pinned in the ejection port by the bolt face.
To resolve a stovepipe jam that you have visually identified, you may simply be able to sweep across the ejection port and dislodge the offending empty with a simple hand motion. While this may work, you still won’t have a round chambered and ready to fire. It is more efficient to use the “tap, rack and reassess” method, but with the rifle angled with the ejection port down so that you can get a little help from Newton’s friend, gravity. Success with the modified version of “tap, rack and reassess” is easily in the 90 percent range. The other ten percent will require the operator to use his or her fingers to clear the brass by sweeping them though the magazine well. With the stovepipe jam cleared, you may reseat your magazine if you’ve had to remove it, rack the bolt back and release it, readying your system to fire.
The third and most complicated type of stoppage is the “double-feed.” If you’ve followed proper procedure, you’ve just done a “tap, rack, and reassess” cycle and found that your AR-15 is definitely not ready to fire. In fact, you’ve got something akin to a log jam happening in your receiver. This is a double-feed.
How to Clear a Double Feed
The double-feed is only made worse by the fact that your buffer spring is keeping pressure on the problem. The first thing you will need to do is pull the bolt back and lock it in the rearward position. Once you’ve taken the pressure off the stuck round(s) you’ll need to rip out your magazine. While we consider the double-feed a simple stoppage, magazine function often contributes to this type of stoppage. Now, with the magazine out, rack the bolt back, maybe two or three times to ensure you’ve applied the needed force to the situation. If an application of “lock, rip and rack” doesn’t work, you’ll have to dig in the magazine well with your fingers to clear the offending rounds.
Double-Feeds and the 30-Round Magazine
If you have frequent double-feeds and you’re a fan of 30-round mags, you just might be creating your own malfunction. Since nothing’s really “wrong,” we’ll deal with it here, as a simple stoppage. If you spend enough time around tactical guys, you’ll find out that the average buffer spring in an AR-15 isn’t as strong as you might think. What happens when you’ve got a tightly loaded 30-round mag is that when the buffer spring isn’t strong enough to push the round all the way into the chamber and you end up with a round halfway out of the mag. Now, the bolt isn’t far enough along to use the forward assist to complete the cycle so what do you do? That’s right, cycle it again. That’s when it picks up the second round and you’ve got a beauty of a double-feed on your hands. Prevention? Yes, prevention is the key to this one. Just don’t load those big mags clear full. There are plenty of guys running 29 rounds in 30-round magazines who never have to figure out how to clear a double feed.
Malfunctions in the AR-15
A malfunction is a failure of the mechanical, or working parts of the AR system or a failure of the ammunition itself. AR-15 malfunctions may be due to an irregularity in the performance of the rifle itself, the magazine used to deliver ammunition to the rifle or a problem with the ammunition itself. There are several common categories of malfunction. The most common AR-15 malfunctions are: failure to feed, failure to fire, short stroke, failure to eject, and failure to extract.
Failure to Feed / Chamber
A failure to feed is a malfunction that can happen as you initially load your rifle or during a firing cycle. A common cause of failure to chamber is that the bolt carrier group has not moved forward with enough force to complete the operation of feeding/chambering ammunition or to lock the bolt in place. In this case, you may be able to resolve your problem with a simple “tap, rack and reassess,” but if the failure recurs with any frequency, it is likely your rifle has a true malfunction that needs to be addressed. There are a number of things that can contribute to failure to feed/chamber malfunctions.
If you are having issues with failure to feed, you may find that you have a common problem with your magazine. Before you go any further, simply be sure that your magazine is loaded properly and solidly seated. If In doubt, rip it out and replace it with another fresh magazine.
There is a school of thought that believes the proper loading of a magazine is an art of sorts. You need to be sure you are using enough force to properly seat the magazine without being so rough that you dislodge ammunition. You can misalign the ammunition inside the magazine or, if it’s backed by a strong magazine spring, you could even knock loose a round to try to jump into the chamber prematurely. Either of which will inevitably cause AR-15 jamming. Once in place, tug on the magazine to be sure it’s properly engaged with the magazine catch. Using the Tap & Tug loading procedure is second nature to many shooters, and can help the shooter new to the AR platform to avoid a lot of issues that might look like a feeding malfunction at first blush. Categorized as a failure to chamber or feed, the simple problem of an improper lock due to a magazine that is either setting against the ground or influenced by forward pressure will create a malfunction that is easily remedied by using tap and tug and keeping your magazine clear of the ground and other obstacles.
If you’ve ruled out a routine loading issue, but swapping out magazines resolved your malfunction, there are a few things you can look for when you get back to the suspect magazine. If it is dented or bulged, the magazine may not allow ammunition to move properly into the rifle. Check the function of the magazine spring. A weak spring may not have the force required to push the ammunition into position to be pushed forward into the chamber.
If there is nothing obviously wrong with the magazine, there are a couple of other problems that are commonly experienced with larger volume magazines. Where 30 round magazines are involved in repeated stoppages and feeding malfunctions it’s not uncommon to find a specific problem:
There isn’t enough room at the top of a fully loaded 30-round magazine for the magazine catch to take hold of it and the spring is already depressed so far that there is no give. In this case, you might get the first round off, and then the magazine falls away, knocked loose by recoil. The fix for this is the same as the magazine-bred double-feed. Up for a few 29-round mags, anyone?
Buffer Spring Problems
Assuming you’ve ruled out magazine issues, you may have a damaged, worn or completely broken buffer spring. All you can do for this one is head back to the bench, brake the rifle down, and replace that spring with a quality replacement buffer spring like the one offered in Spike’s Tactical AR-15 Buffer Tube Assembly Kit. Drop-in replacement springs are often of a lot better quality than most springs that are original equipment in many builds.
Defective Rounds / Ammunition Borne Feed Malfunction
Defective rounds can cause a number of different versions of the failure to feed family, but there are two ammunition failures that are more common than the rest. Stubbed rounds are no fun. When the bullet has been forced back into a cartridge, it’s likely to hang up on its way forward or go any way but straight causing a jam. Even more fun than Stubbed rounds, are cartridges that have separated on extraction, ejecting a partial cartridge and leaving the balance in the chamber. Assuming you’ve already attempted the “immediate action” routine and you’re up against some resistance you’ll need to do the following:
- Pull the bolt all the way back and lock it in place.
- Pull the magazine
- Clear the chamber of the damaged round.
While that sounds simple enough, you need to understand that sometimes these things are really stuck in there. It may take the patience of a saint, more than a few choice words, and smithing tools to extract an ornery piece of brass. After a difficult episode with a piece of damaged ammunition, be sure to check for safe function of your firearm before resuming operation.
Brass Over Bolt (Bolt Override): Everyone’s Favorite Malfunction
While this one isn’t as common as some others, it’s one of those malfunctions that spawns a jam that everyone on the range makes out to be a national emergency. Somehow a piece of spent brass (or for variety and excitement, a live round) becomes lodged above the bolt in forward position and immediate action isn’t happening because the charging handle won’t budge. On examination the operator identifies a bolt over brass malfunction.
- Attempt immediate action, discover that charging handle won’t move, and identify brass over bolt condition.
- Drop the magazine.
- Move the bolt into the rear position by keeping pressure on the charging handle and bumping the butt of your rifle on the ground. It will require fairly aggressive handling to gain the space you will need to clear the stuck round.
- Reach through the magazine well to push a finger (or a tool) against the bolt face. Apply steady pressure. Take hold of the charging handle and move finger from the bolt. Strike upward against the charging handle taking care not to break it. This should allow the round to come loose. Pull the bolt to the rear position and the round should fall away.
The correction of a brass over bolt malfunction requires a bit of force, but it really isn’t a dire situation. Be calm and work the problem.
Failure to Feed Due to Dirt, Debris, and Fouling: Short Stroke
As a gas operated weapon system, the AR-15, operates best when kept clean and well lubricated. Accumulation of “fouling,” soot and debris that are a by-product of firing the rifle itself can cause a failure to feed malfunction by slowing or restricting the movement of the bolt carrier group, causing it to fail to cycle completely rearward. Likewise, excess dirt on the lower receiver extension (buffer tube) or a fouled gas tube may have a negative impact on the ability of the system to function. Many gas system issues will produce a particular malfunction causing a short stroke or “short recoil.” This malfunction of gas management systems creates excess back pressure so that the bolt carrier group is not forced through the full rearward cycle as required to feed subsequent rounds. Simply put, dirty weapons often short cycle, either due to friction or binding of the bolt carrier group or because fouling or dirt increases back-pressure on the gas system to a level that cushions the action of the bolt rather than allowing it to cycle backward to its fullest extent. Gas systems are also at risk of not holding enough pressure to properly cycle when they become fouled. Moral of the story, clean, properly maintained rifles rarely short cycle. Dirt, debris, and soot are an invitation for failure to feed malfunctions.
Failure to Fire
Failure to fire is a fairly small category of malfunctions suffered by the AR-15. If a live cartridge is loaded into the weapon, properly chambered, and the operator has pulled the trigger to release the hammer a round may fail to fire. There are two causes of failure to fire that are at fault in the vast majority of this category of malfunction: Either the ammunition itself is defective or the firing pin has not struck the primer hard enough to trigger the initial explosion that ignites the powder inside the casing.
As always, perform immediate action to attempt to resolve your stoppage. If the malfunction recurs, you will need to complete troubleshooting and address the problem.
In order to determine which cause has created your failure to fire malfunction, inspect the round which failed to go off. Looking at the primer of the round in question, note the depth of the mark left by the firing pin striking the primer. It may be helpful to compare the primer to that of an empty cartridge that was successfully fired. If the indentation in the primer appears to be of normal depth, the round is defective and should be disposed of safely. If the primer is unmarked or the indentation is significantly shallower than normal, there is a problem with the function of the firing pin.
Diagnosing Firing Pin Faults
Like many other AR-15 malfunctions, failure to fire malfunctions that are due to a firing pin malfunction are frequently caused by a buildup of by-product from the combustion of propellant, or fouling. If you inspect the firing pin and find no obvious defect, your best bet is to clean the weapon being sure to pay special attention to the firing pin, bolt and bolt carrier, as well as the area of the barrel extension locking lug. Obviously, if you do find damage to the firing pin, it will require replacement.
If you are shooting and experience a situation in which there is unusually weak recoil or a weak “pop” rather than the weapon’s normal report, you should stop immediately and lock the bolt to the rear. DO NOT try immediate action. Once the bolt is locked back move the safety selector to the safe position and take out the magazine. Once the rifle is secure, look into the barrel to see if the bullet is lodged inside. If you can see that the barrel is obstructed your rifle will need to spend some time on the bench, this isn’t a field serviceable malfunction.
Failure to Extract
While failure to fire might seem to be a serious malfunction, failure to extract can have much more serious results if the problem is not readily identified. It is possible that an unfired cartridge could be in the chamber. If you were to feed another live cartridge you could create a catastrophic explosion. That’s almost certain to cause the kind of injury that could end your shooting career. Moral of the story: failure to extract can be serious business and should be treated accordingly.
When a failure to extract occurs, the bolt and bolt carrier may short stroke, or they may return completely rearward. In either case, a cartridge is left in the chamber. On the next cycle, a live round may be fed and forced into the base of the case that was left behind. This malfunction can be difficult to resolve. The remedy will depend on whether the cartridge is actually stuck in the chamber and if another round has been fed.
- Lock the BCG to the rear of the action and change the safety selector to safe.
- Remove the mag and any loose cartridges.
- Bump the rifle butt stock on a firm surface to dislodge the remaining round.
If the case has broken or ruptured, it is likely to be stuck in the chamber. If it is:
- Place a cleaning rod in the barrel from the muzzle end.
- Tape the casing with the cleaning rod to chase it back out of the chamber.
There are several causes that may be identified for extraction failures:
- Short Recoil – see the section above on short stroke due to dirt, debris, and fouling.
- Fouled or Corroded Chamber – Inspect and clean, then determine if the chamber is damaged or safe to return to service. If it is damaged, the barrel will need to be replaced.
- Weak or Broken Extractor Spring – replace spring that is no longer serviceable.
Failure to Eject
The end of cycle malfunction. The cartridge that should have been ejected does not exit through the ejection port, but either stays part way in the chamber or ends up jammed into the upper when the bolt comes forward. Most of the time this malfunction is caused by short stroking (we covered short recoil earlier) or fouling or corrosion of the chamber which cause friction on extraction throwing off extraction and ejection functions.
Resolving Failure to Eject Malfunctions
In most cases, you will find that a simple pull of the charging handle will free the brass that failed to eject, you need to be sure that live round hasn’t been fed either partially or completely into the chamber. If a live round is present, the magazine and all live cartridges will need to be removed before you can release the charging handle. If the failure to eject malfunction is a recurring problem and it is not resolved by giving your weapon a good cleaning and proper lubrication treatment, it is best to just go ahead and replace the ejector and extractor springs as well as the extractor.
After looking at the most common stoppages and malfunctions of the AR-15, you really need to take away two things: The AR-15 functions best when kept clean and lubricated, don’t neglect basic rifle hygiene! Good quality AR-15 parts will save you a lot of trouble. Strong springs, components with quality finishes and parts that fit properly are essential for trouble free operation of the AR-15 weapon system.