Since the AR-15 became the M16, the U.S. military rifle and carbine (sort of) in service for longer than any other, there has been a debate over the necessity of a feature that didn’t exist on any prototypes or early versions of the AR-15 or the AR-10 before it: the infamous forward assist.
One would think an “infamous” design feature would be the result of an engineering debate or a quirk of the manufacturing process—but in this case, the reasons are almost entirely bureaucratic.
What It Is
The charging handle on an AR is a one-way affair. You pull it back to retract the bolt carrier group, release it, and the buffer spring pushes the BCG forward to chamber a round and put the gun into battery. Or, with the bolt locked open, you insert a magazine and press the bolt release, which chambers a round and puts the gun into battery without touching the charging handle. Alternately, you can pull back on the charging handle if the bolt is locked open, which will disengage the bolt release, and then release it, like slingshotting a slide on a handgun.
(On early AR-15s and AR-10s, the charging handle was located on top of the receiver and shielded by the carry handle, but the military requested the location be changed. I’ve heard it was because the charging handle got too hot after sustained fire, but I can’t imagine it getting any hotter than any side-mounted charging handle, so who knows.)
If the BCG is in the forward position, meaning a round should be chambered, the charging handle can only retract the bolt, as it isn’t attached to the BCG.
So, to allow soldiers to manually push the bolt forward, the same way they could with the M1 Garand, M1 Carbine, and the M14, a series of teeth were cut into the right side of the BCG. A port was added to the right side of the upper receiver behind the ejection port containing a spring-loaded plunger with a push handle. When pressed or tapped, a wedge on the front of the plunger engages the teeth on the BCG at an angle, forcing the bolt forward enough to, theoretically, chamber a round that isn’t completely seated. This, is the “forward assist” (FA). You can get a visual representation of how it’s intended to work in the clip below:
Why Would This Be Necessary?
There are a number of reasons a round may not fully seat in a chamber. Out of spec or defective ammunition is one, a damaged or obstructed chamber could be another, debris could be getting in the way, there could be a magazine or feed issue—a heavily fouled chamber could also potentially prevent a round from seating.
If you want to actually see an FA work, grab an AR and a few dummy rounds or snap caps in a mag. Lock the bolt open, insert the magazine and, instead of slapping the bolt release, pull back on the charging handle, and slowly let it move forward, picking up a snap cap and chambering it. If you do it slow enough, it will end up just barely out of battery. Tapping the forward assist should push it the rest of the way. That’s really all there is to it.
Eugene Stoner, the man who designed the rifle, said it was utterly unnecessary and that, during the millions of rounds fired during the development of the AR-10 and the AR-15, he never saw a situation arise that would have been solved by the FA. The U.S. Air Force pretty much said the same thing. About a thousand Colt AR-15s without a forward assist were used by South Vietnamese troops under U.S. advisors in 1962 before the adoption of the M16 and they did not report issues that would have been fixed by an FA.
So Where Did It Come From?
The Air Force was the first branch of the service interested in the AR-15. While the army was busy trying to get the M14 to work out after shooting down the AR-10, the .308 Win. predecessor of the AR-15, the Air Force, now it’s own service branch, wanted to order 80,000 AR-15s from Colt to replace the aging M2 Carbines their security personnel were using, but the request was denied because: bureaucracy.
Eventually, in the early 1960s the army got hip when the brass realized the M14 program wasn’t working out and it was cut short before enough of the rifles had been made to arm all of the armed forces, who were otherwise using WWII-era firearms.
With the situation in Vietnam heating up rapidly, the decision was made to buy 80,000 AR-15 rifles and adopt them as the M16. By 1965, the military had purchased at least 300,000 of the rifles. But the army wanted some changes first. The most dramatic alteration they requested was the inclusion of a “manual bolt closing device,” a mechanism that would allow a soldier to force the bolt into battery if, for some reason, a round failed to chamber completely.
From everything I’ve read, experts I’ve spoken to, and the testimony that was given regarding the M16 during the congressional investigation held about the rifle’s early problems, it seems the only rationale for this was that every other modern rifle the military had ever used to that point (the bolt guns, the M1 Garand, the M1 Carbine, and the newer M14) had a charging handle attached directly to the bolt, making it possible to manually push the bolt forward.
It was part of the small arms manual and the way shooting had been taught in the military since the Second World War. Hell, the action on the M1 Garand was supposed to close once a new clip was inserted, but in combat conditions, it often stuck and the charging handle needed a little slap forward to send it home.
In the late 50s, army brass really wanted the M14 to work. They even held a test, which was later proven to be biased, just to prove the M14 was better than the AR-15 after the latter was recommended by the Advances Research Projects Agency after the testing with indigenous troops in Vietnam.
By 1963, the new Secretary of Defense, Robert McNamara, had taken control of ordnance away from the army, for the most part, and the Green Machine was being “forced” to adopt a rifle made of space age aluminum alloys and plastics that was half the weight of the M14 and fired a tiny cartridge compared to the 7.62 NATO and .30-06 rounds that came before the 5.56 NATO.
Not being able to manually manipulate the bolt may have simply been too much. It may have represented a line in the sand for the army’s willingness to accept change at the time.
Whatever the motivations, the Air Force didn’t think the forward assist was necessary, and they got about 19,000 M16s without the appendage—while the bulk of the first order went to the army and were built as XM16E1 rifles, which included the forward assist. The feature remained on the M16A1, A2, A3, and later, the M4 carbine.
After all these years, and the lack of “a forward assist saved my life” stories, most folks see it as a sort of appendix of gun features, an unnecessary thing that never should have been included in the first place, but others maintain that it’s an essential element of the AR design that is absolutely necessary. I don’t agree with that.
It’s an additional point of potential failure. The only thing holding the FA together is a small roll pin. With many service members taught that the FA has to be slapped upon every reload, it has a tendency to break eventually, letting the FA interfere with the BCG, and cause serious jams.
Conversely, if it’s never used and never breaks, then it’s just another protrusion to get caught on things and to add extra weight to the upper receiver.
On top of all that, if someone is firing from cover or concealment and something inadvertently presses on the FA, it won’t damage the gun, but it can certainly prevent the bolt from cycling if it’s pressed with even moderate force.
I have never used a forward assist on any AR and have never had a reason to. I have put thousands of rounds through my IWI X95, a 5.56 bullpup rifle that has no way to manually push the bolt forward, and on that platform, I’ve also never had the need for such a device.
Why Do People Still Like the Forward Assist?
One reason people hang on to a need for the forward assist is habit. For decades, soldiers and Marines were taught the FA was an integral part of the loading process of the M16. As you can see below, it was literally part of the M16A1 army manual. This was engrained in a lot of people, as training will do, and they brought it to the civilian shooting world.
On the civilian side, one of the most reasonable justifications presented by keyboard warriors in favor of the forward assist is that, when hunting, it allows them to get set up and chamber a round quietly (as described above) without the clang of the bolt snapping shut, letting them know for sure the gun is ready to fire.
That’s all well and good, and a hunter certainly shouldn’t, say, climb into a treestand or a blind with a chambered firearm—but you don’t need the forward assist to do this quietly.
You may have noticed an indent in the exposed side of every AR bolt carrier group. It’s visible in the ejection port when the gun is in battery. If there is no malfunction and you simply closed the bolt slowly and the round isn’t fully seated (most of the time, if the gun is clean and lubed, it will simply chamber no matter how slowly you do this) putting your thumb in this indent and pushing forward will allow the round to be fully seated, then you flip on the safety and close the dust cover. That’s why the indent is there.
How can you tell for sure that a round chambered successfully? You’ll know when you flip the selector switch to “safe.” The safety on an AR cannot be engaged unless the gun is in battery. If it flips to the safe position after loading, all is as it should be.
I agree with Stoner, who said if a round doesn’t seat fully during the normal operation of the rifle, then forcing it into the chamber and firing is not a good or safe solution. Instead, eject the round and chamber another, or look for a malfunction if that doesn’t work.
Why? If there is an issue where something—fouling, dirt, or whatever—is making the chamber tighter than it should be, a cartridge forced into that chamber and then fired, expanding the brass, dramatically increases the chances for a failure-to-extract jam. And that kind of jam nearly always requires disassembly and a cleaning rod to fix. Better hope that one shot was perfect, and all that was needed.
If a round is stuck so bad that you have to mortar the gun to eject it, then you definitely shouldn’t force it into the chamber to be fired.
(It is really interesting to note that the final iteration of the AR-10 known as the “Portuguese Model” actually did have a forward assist. At the time, the .308 version of the design still had a non-reciprocating charging handle on the top of the receiver, inside the carry handle. If you pushed down on the front of the charging handle, it would engage with teeth cut in the top of the bolt carrier group. By the time the AR-15 had been developed in 5.56, the feature had vanished, though a similar device was later proposed at the Army’s request along with the plunger-style forward assist.)
You might say, “Well, in a life or death situation, it’s better to be able to force the chamber closed and at least fire the round.”
I would counter by saying, in such a situation, if you have the presence of mind to identify this as the issue and slap the forward assist when such a malfunction occurs, you would be better off pulling the charging handle, ejecting the round, and chambering another.
And again, if the chamber doesn’t fully chamber the first round of a fresh magazine, which sometimes happens if, say, a strap gets in the way of the charging handle on its way forward or whatever, that’s what the aforementioned indent on the BCG is for. If more force that you can exert here is needed, the round shouldn’t be chambered.
There is one other argument in favor of the FA that does have some merit. I’ve heard veterans every so often say their charging handle would get hooked on their gear and pull the bolt out of battery, and tapping the FA every so often was a way to make sure the gun was ready to fire without opening the ejection port cover.
OK, in combat, sure, I can see using the FA this way providing some comfort on patrol. But if the charging handle and the latch that keeps it in place are repeatedly being engaged by your gear in such a way that it takes the rifle out of battery, then you have to rethink your gear set up.
Also, while not sleeping and thinking about this, I put on a plate carrier with mags and tried really hard with two different ARs to get the charging handle to pull the bolt out of battery without also opening the dust cover (using .223 snap caps), and I just could not do it. Point being, if this happens, glancing at your ejection port and seeing the dust cover open will tell you something could be amiss. Additionally, the FA certainly does not work all the time. Just tapping it without visually inspecting the chamber is pointless.
What I’ve Learned
The forward assist is not a necessary part of an AR-platform rifle, carbine, or pistol. The only logical conclusion is that all ARs should be side-charging, and we could stop having this argument all together, leaving the forward assist in the gun history bin where it belongs.
But seriously, Stoner knew this was the way to go when he denounced the FA on the XM16E1 and designed the AR-16, which eventually became the AR-18/AR-180 sold by ArmaLite and Colt, with a side-charging handle—and no forward assist.
UPDATE Aug. 11, 2020:
And lo and behold, Gun Jesus himself graces us with a concise run-down of the history of the forward assist on the AR-15: