What Eugene Stoner Had To Say About The 5.56mm
BY Herschel Smith
5 years, 4 months ago
Except the last part, this is a good history lesson.
“At a distance of approximately 15 meters, one Ranger fired an AR-15 full automatic hitting one VC [Viet Cong guerrilla] with three rounds with the first burst,” one report read. “One round in the head — took it completely off. Another in the right arm — took it completely off, too. One round hit him in the right side, causing a hole about five inches in diameter.”
Another run-in detailed five kills with AR-15 rifles — “back wound, which caused the thoracic cavity to explode; stomach wound, which caused the abdominal cavity to explode; buttock wound, which destroyed all tissue of both buttocks; chest wound from right to left, destroyed the thoracic cavity; heel wound, the projectile entered the bottom of the right foot causing the leg to split from the foot to the hip.”
The guerrilla whose buttocks had been blown off lived approximately five minutes, according to the report. The other four were instantaneous kills.
“Two were killed by AR-15 fire,” read another Special Forces report to ARPA. “Range was 50 meters. One man was hit in the head; it looked like it exploded. A second man was hit in the chest; his back was one big hole.”
[ … ]
“The reason I asked that question, one Army boy told me that he had shot a Vietcong near the eye with an M-14 and the bullet did not make too large a hole on exit, but he shot a Vietcong under similar circumstances in the same place with an M-16 and his whole head was reduced to pulp,” Ichord said. “This would not appear to make sense. You have greater velocity but the bullet is lighter. The foot-pounds are still going to be less, if it is lighter.”
“There is the advantage that a small or light bullet has over a heavy one when it comes to wound ballistics, even for the same velocity. But, of course, the velocity helps,” Stoner replied.
“What it amounts to is the fact that bullets are stabilized to fly through the air and not through water or a body which is approximately the same density as water,” Stoner continued. “And they are stable as long as they are in the air. When they hit something they immediately go unstable. In other words, your spin rates are determined in air, and not in fluid.”
A .30-caliber M-14 bullet might stay stable through the human body, Stoner said, “while a little bullet, being as it has a low mass, it senses an instability situation faster and reacts much faster. So, therefore, this is what makes a little bullet pay off so much in wound ballistics. As soon as it gets into an unstable portion, it tends to tumble faster, because its mass is lower.”
And then the author goes off the rails. “This history is fundamental to debates over gun reform. The AR-15 and its cartridge were designed together to create a rifle optimized to kill humans, but the rifle and ammunition have since become a mainstay of civilian hobby shooters. This isn’t a new revelation. Eugene Stoner knew exactly what the gun was supposed to do when he designed it 62 years ago.”
As if we don’t have a right to own whatever the military owns! I think the constitution says something about that, yes?
On August 30, 2019 at 7:26 am, Bram said:
I was always a bit skeptical of those early story about how devastating the M16 was in Vietnam. I think the proper description would be “unpredictable”. With a 49 grain bullet out of a low-twist 20″ barrel at 3250 fps – anything could happen. From a small flesh wound to a big meandering hole.
But nobody is buying AR’s with those kinds of barrels now and most people are shooting heavier more stable bullets. I’d still fear being shot with an M14 a lot more.
On August 30, 2019 at 9:25 am, revjen45 said:
The 52-55 gr load with 1:12 gives the most effective terminal ballistics. It is on the edge of stability in air, thus loses stability @ -40 – -60 deg.f. I will never need to worry about accuracy at such temperatures, so that load works for me for SD/HD.
On August 30, 2019 at 1:12 pm, TRX said:
> “One round in the head — took it completely off. Another in the right arm — took it completely off, too. One round hit him in the right side, causing a hole about five inches in diameter.”
—
Where can I get some of those magic bullets?
Neither my .45-70 nor my .500 Nitro Express perform like that!
Do they turn in mid-flight like the 6.5 Carcano Oswald had? I saw the shooter in a movie flip the barrel to the side so the bullet would fly in a curve, but it’d be better if it just did it by itself…
On August 30, 2019 at 1:22 pm, TRX said:
BTW, though it’s usually implied that the 5.56×45 broke new ground as far as bullet yaw causing a larger wound path, Sir Alfred Greenhill codified the math in 1879, though the concept had been known to British sportsmen for decades. If you’ve ever wondered why some of the rifles in the old old “Africa” calibers (like the .500 I mentioned previously) have absurd twists, it was because the designers didn’t want the bullets to be any more stable than needed for point-blank accuracy. Having only recently moved from smoothbores, they determined their optimum twists by having barrels made and then shooting stuff with them to see how they performed. The gun cranks of the day fairly burned up the letters pages of British gun magazines debating what twist was most effective for which game.
On August 30, 2019 at 4:05 pm, Pat Hines said:
Some folks just can’t accept both test results and real world documentation. It’s a case of “my daddy used .30 caliber, so it’s .30 caliber for me”. I also have a secondary issue with those that prefer the M1A/M14 over the AR-10/308/FAL because of “wood” versus plastic.
If it wasn’t for the invention of the bore snake, M1A/M14 shooters would still be cleaning the bore of their rifle backwards from ideal.
The AR-15/M16 has been in use in the US military longer than any previous issued rifle, deservedly so. It is the de facto standard rifle in the US and will remain so for many decades.
On August 31, 2019 at 1:05 am, Georgiaboy61 said:
Re: “If it wasn’t for the invention of the bore snake, M1A/M14 shooters would still be cleaning the bore of their rifle backwards from ideal.”
Pat, love yourself some M16’s and dislike yourself some M14’s – but the direction in which the bore is cleaned has nothing to do with the choice. Whenever possible, it is desirable to clean from the chamber to the muzzle, and not vice-versa. Why? So that you do not damage the crown of the muzzle, the last thing the bullet “sees” as it exits the barrel, thereby greatly effecting accuracy and down-range performance. This is why Brownells, Midway USA, et al. make money selling bore guides, too. Save that barrel, save that crown!
There are plenty of pull-through cleaning options which make sense for either platform. Nor is there anything wrong with old-school cleaning rods, jags and patches, bore brushes, Hoppes #9, etc. Whatever rocks your boat.
Perhaps it makes me a heretic, but I happen to like both platforms – the M14-pattern rifles, and the AR15s/M16s/M4’s which replaced them. Like any tool, each type of rifle has its place and mission. The crux of the matter is for the soldier, sailor or Marine to have the right one in his hands when he needs it….
Our recent (national) experiences in places like Afganistan tends to prove out my thesis that neither battle rifles nor assault rifles alone are sufficient for the typical grunt squad, platoon, or other small unit. Our enemies, contrary to popular belief, are not stupid, and they study how our guys prefer to fight.
If we want to use our 0-300m capable assault rifles, carbines, and SBRs, then hajji will engage us preferentially from 300-600 meters, at which distance their full-power centerfire rifle cartridges – typically British .303 and Russian 7.62x54R – hold a significant advantage in range, accuracy and power.
The Soviets, who by the late 1970s and 1980s, had largely converted to their analog of the 5.56×45 NATO, the 5.45×39, learned the same lessons in the sandbox as our guys did later on. Battle carbines and assault rifles, while excellent weapons, are not the answer to every infantryman’s problem. They will often suffice, but not always. Flexibility is the key.
On September 1, 2019 at 6:40 am, SWRichmond said:
“Our recent (national) experiences in places like Afganistan tends to prove out my thesis that neither battle rifles nor assault rifles alone are sufficient for the typical grunt squad, platoon, or other small unit. Our enemies, contrary to popular belief, are not stupid, and they study how our guys prefer to fight.”
This
On September 1, 2019 at 1:10 pm, SemperFido said:
Stoner’s original design was for a .308 caliber weapon. He switched it to .223 at the insistence of the Pentagon rifle assessment team.
Anecdotal stories about how devastating wounds were achieved with the mouse rifle are balanced by similar tales of men who displayed severe wounds such as head shots who kept on fighting and skinnies having the .223 go right through them with minimal effect.
Part of the problem is the type of bullets used. Dictated by the Geneva accords pointy bullets just don’t do the same amount of damage as hunting rounds do.
And Georgiaboy is right. Flexibility in mission requirements is key. No one rifle or round will do it all.
On September 1, 2019 at 11:31 pm, Georgiaboy61 said:
@ SemperFido
Re: “Stoner’s original design was for a .308 caliber weapon. He switched it to .223 at the insistence of the Pentagon rifle assessment team.”
In the mid-1950s, at the insistence of CEO George Sullivan, Armalite included an experimental prototype rifle with a composite steel-aluminum barrel along with the other AR10s submitted for the Ordnance Dept. small-arms trials to determine our new service rifle. This was done over the vehement objections of Armalite Chief Engineer Eugene Stoner, who believed – correctly as it turned out – that the hybrid barrel was not yet perfected and ready for use.
The composite barrel rifle failed catastrophically during testing, and although Armalite reacted quickly to fix the problem, the damage was done and the AR10 was dropped from further consideration after a promising start.
Ultimately, Armalite was forced to license the AR10 design to other firms, in order to generate at least some revenue from the design. One of these was the Dutch firm of Artillerie Inrichtingen (hereafter AI), which made some common-sense improvements to the rifle to beef it up, make it more-durable and otherwise prepare it for field use. Dutch engineers and technicians gave the rifle a stouter buffer assembly, and made some other small changes as well.
AI managed to sell some of their AR10s to the Portuguese military, who elected to equip their elite paratroopers with the Armalite rifle. The ‘Paras used their AI AR10s in heavy combat action in Angola and other African “bush wars” throughout the 1960s and into the 1970s, before finally being forced to turn them in for replacement weapons. The Portuguese AR10s were tough, durable, hard-hitting, accurate, light-in-weight and surprisingly easy to use even in full-auto (select-fire) mode.
The Paras loved their Artillerie Inrichtingen AR10s so much that they paid for locally-fabricated spare parts to be made when official sources of spares dried up and they become unavailable. A testimony to the esteem in which they held the rifle, which they preferred to the CETME/G3’s being used elsewhere in their nation’s military, as well as the FN FAL and other competitors.
Although Armalite never perfected the AR10, the design reached its final and best iteration at AI, who showed the full potential of this system as a lightweight, modern and capable battle rifle. Even today, more than a half century after Armalite first developed the AR10, the design compares favorably with modern counterparts.
World-famous marksmen and firearms expert Jerry Michulek recently borrowed for a day at the range a genuine AI AR10 from the collection of Reed Knight, the owner of Knights Armament Corporation, and was floored by the quality, controllability, light weight and ease of handling of this more-than-fifty-year old rifle.
Many firearms historians opine that the FN FAL was the road not taken by the U.S. in the late 1950s. I would argue that it was the AR10. If the Ordnance Dept. had allowed time for the design to be perfected, it might have really been something special in the hands of our fighting men. And if the inclination and funding were there later on, it would have been ideal as a platform for a true intermediate caliber system, something falling in-between 7.62×51 NATO and the later 5.56×45 NATO cartridge.
On September 2, 2019 at 1:41 pm, Yog said:
Something to keep in mind was that very early AR rifles had a 1-14″ rifling twist. This was the original rifling twist that earned loyalty from the soldiers who used them.
When the twist was changed from 1-14″ to 1-12″ some of that fantastic lethality was sadly lost.
On September 2, 2019 at 4:45 pm, Herschel Smith said:
Twist changed for [a] shorter barrels, and [b] heavier bullets, up to 67 gr., the weight of tracer rounds.
And yes, that’s right.
On September 3, 2019 at 12:13 pm, Bram said:
I’d say the real road not taken was the .276 Pederson and the Brit .280. The Army is like a crappy shooter with bad breath control. They keep missing high or low.