Reliability of the M16 during the design phase

In a comment to my post on the XM8 James Rummel (who runs the excellent Hell in a Handbasket site) responded to ACE‘s question about the advertised reliability of the M16 when it was being developed. I did a quick search and came up empty, but Mr. Rummel knows his guns. He wrote

It would appear that it was touted as perfectly reliable. There’s even a well known story about how they didn’t include cleaning kits with many M16’s because they said that it never needed to be cleaned at all! This meant that a vast number of rifles were marked as defective when they started to jam and had to be replaced entirely.

Now, I wouldn’t dare to doubt Mr. Rummel when it comes to firearms, but I found the idea that M16 would have been issued without cleaning kits to be incredible. I mean, everyone’s heard horror stories about jamming M16s in Vietnam, but NO CLEANING KITS? Come on!

Well, Mr. Rummel. Slap me down. Hard.

A further search (using Google, not Booble) turned up some more info. This site writes

On 16 June 1966, Colt was awarded a contract for nearly 840,000 rifles for $91.7 million, assuring the M16’s future. But between 1965 and 1967, several major problems, centering on the direct gas action and the lack of maintenance equipment, occurred with the M16 in combat because there was no one entity to manage the overall production process of the M16.

The use of ball gunpowder left a very sticky residue in the barrel and the gas tube of the M16. Since the barrel wasn’t chrome-plated and no cleaning equipment and/or lubricants were available, it hardened quickly and soon made the rifle inoperable. The residue also caused spent casings to become stuck in the chamber and the rifle suffered a rim shear extraction failure, where the bolt’s extractor tore off a portion of the end of the spent casing, leaving the rest of the case stuck in the chamber. Because of the ball gunpowder’s ballistic characteristics and the rifle’s buffer’s light weight, the M16 fired fully automatically with a cyclic rate of between 850-1000 rounds per minute, well in excess of the normal 750-850 rounds per minute. Compounding this comedy of errors was the lack of training and instruction given to those troops who were issued the M16.

And this page has

The only major problem that was not discovered yet was that the Army told its soldiers that the M16 need not to be cleaned. This would have been true if the Army had used the ammunition the M16 was designed for, but instead the army used cheaper ball powder, which clogged up the barrel and lead to malfunctions of the rifle. From Ezell’s book I quote:

When Stoner developed the 5.56mm cartridge, he used a commercial gunpowder called Improved Military Rifle (IMR) powder. Stoner had used this extruded gain propellant because it was cleaner-burning than the ball type specified by the Ordnance Corp. …transmitted powder residues that tended to dirty up the bolt and bolt carrier assembly, and in turn jam the rifle.”

This was quickly taken care of by issuing cleaning kits to the soldiers.

Amazing. Simply amazing. Given the extraordinary claims made by many involved with the XM8 testing, I hope we’re not repeating history here.

Mr. Rummel, I apologize for ever doubting you. Thanks for the tip.


  1. I had heard about this some years ago. Aside from the idiocy of no cleaning gear for any weapon(everything will need cleaning sooner or later), the jams caused all kinds of BS to be handed around, such as that you had to oil the ammo- which really helped.

  2. Holy Poop! And here we are 38 years later, talking about what had to have gotten a lot of troops killed. Sheesh! Have heard about problems with USAR’s Beretta 9mm pistol involving slide breakage under sustained fire. Wonder how many that’s accounted for? Also, if AK-47 was 7.62 mm, how could relatively puny M16 5.56 mm cartridge keep up? These loads are nowhere near equal. Regards. Roger

  3. I have always heard that the M-16 ammunition was designed or ‘re-designed’ specifically to have more tumble after target penetration. Can anyone verify this or point me in a direction where I can find verification? Trying to settle a wager. Thanks.

  4. I have answers to a few questions posted on this site. Relating to the M-16 and the tumbling ammunition the M-16’s ammo does do that but that was not disigned purposly it was a unintended by-product. Relating to the comparison between 5.56 and 7.62. Size isn’t every thing. The 5.56 x 45mm can punch through body armour but because it is so small it punched right through people and therefore has no stopping power. The 7.62 x 32mm ammo is also powerful, it has more stopping power but because of the shorter case isn’t that powerful.

  5. the 5.56 does tumble when it hits the target, and many people have been told that the tumble is by design. it’s not, the tumble is a product of physics. when the bullet hits, the front stops, but momentum keeps the rear in motion. up, down or sideways offers the least resistance, so the bullet begins to spin, much as a car does when it hits something stationary at high speed. all full metal jacketed bullets tumble, be they 7.62, 5.56, or .38. origanaly, the 55 grain bullet the m16 was meant to use would fragment into two pieces along the chanulure, in effect producing double the wound path, however the 55 grain hyper velocity bullets were unstable and therefor inaacurate in flight, so the army procured the current 77 grain bullet, increasing accuracy but reducing leathality. the m16 was not meant to be a super accurate rifle. itake that back. when origanally designed as the ar10, the rifle was meant to fit the role of a designated marksmans rifle (sort of a half-ass sniper), while the m14 remained the mainstay. however, what was ‘new’ data at the time showed that standered (read draftee – not ranger, marine or other higher level) infantry did not aim, engaged at below 300 yds, and tended to spray rather than expose themselves for a deliberate shot. it was decided by guys in lab coats that we needed a rifle that could fit this style of fighting – heaven forbid we should invest in training. the 5.56 was selected simply because one could carry a lot of them. the AR10 was turned into the ar15/m16, and history unfolded. now that we have a somewhat more highly trained military, deliberate shots are being taken. the problem is, unless you hit someone dead center in the chest or head, you don’t put them down. The second part of the 5.56 story, something many people have also been taught, is that a wounded man takes up more of the enemies resources. that assumes that he takes care of his wounded, and that he has resourses to begin with. our modern enemies turn thier wounded into human mine suiside claymores. speaking for myself and my marines, give us some scout/squad m14s any day.

  6. I’m sorry but I’m a TOTAL amateur when it comes to this subject. However I’m very interested in learning about this stuff. So, that said would anyone care to explain to me the difference between the m16 and the m14 and why the guy who posted last would prefer the m14?

  7. The adoption of AR-15/M16 is a bizzaire story filled with bureaucratic ignorance and short-sightedness. In fact, the rifle was put into use without a long-period of trial test, which was advocated by the original inventor, Gene Stoner. And during the course of development of this rifle many changes were incorporated into its design without consulting Stoner. Most amazingly, the round, .223 Remington, was atually designed by Stoner under based on the .222 Remington, and was first called .222 Special when Remington made the load as required for weapon tests. Anyone who is interested in this story may read the book ‘The Black Rifle, M16 Retrospective’ by R. Blake Stevens and Edward C. Ezell (asumming that everything written in the book is true).

  8. The m14 is an evolution of the m1 garand (semiauto rifle used by the US during WWII) firing a 7.62mm round. The m16 was a revolutionary new rifle firing a smaller 5.56*45mm round that was based on a higher probability of hit traded for less stopping power and range. There are diehards on both sides who will say that each rifle is by far better than the other. However, in regards to Bone-Doc’s question the 5.56mm round was redisigned for the m249’s m856 tracers. The new m855 round was a less effective round than the original m193 round(it required more flesh before it started to tumble).

  9. sorry, havn’t been back in a while. most of my guys would like M14s because 1) they are totally reliable (when mil spec). to us grunts, the mostimportant thing oover allisthat something goes bang every time. now the 16 has been around awhile, and itsd not terrible, but it is somewhat more sensitive than we would like. a Lot of the initial problems have been at least sorted out, though no truly fixed as they are inheirent in the design of the rifle. following closly on reliability, we want leathality. now again the .223 is ok, but we tend to lean towords wanting god awful overkill. i have no problem getting an m1 to blow the entire top floor off a building to kill one sniper, or throwing twelve granades into a room to make sure there is only hamburger on the inside before i go in. look, a gun is a gun, shoot someone in the head and you win. but its when im running and hes running, and RPGs are going off and smoke and dust is everywhere, and i hit him, but not perfectly, that i worry, and so the bigger the thing i can hit him with, the better. an arm shot with a 16= pissed off bleeding bad guy. an arm shot with a 14 = guy with no arm going into shock. its not really quite that nice, but close enough. with modern ‘tactical’ flash hider compensators, the recoil just is not much of an issue. The corps has bought a bunch of new 16A4’s, so its moot anyway. bottom line -you use what you can to the best effect. shoot first, shoot best, shoot most.

  10. Dear SIr: I would appreciate any assistance you could give me on the problems incurred during Vietnam with the M-16, specifically jamming problems. I am doing a research seminar paper on the problems with the weapon and how much loss of life caused from it. I have just started research on this project and need to find if anything has been published for me to use as primary and secondary sources for my research. I have a few people who I will be interviewing but I need other published articles and books on the subject if they are out there. Any assistance would be sincerely appreciated. CTO1 David L. Pederson, U.S. Navy Retired USAF 12/74 – 01/79, 46150, 81130 USN 10/80 – 02/97, Cryptologic Technician Operations

  11. Sirs….I am doing my final test on my exam and I’m researching about the M14. The problem now is lack of pictures of M14 being used in the field. Could anybody give me links for that. TQ.