AR15/M16 Evolution

[SmeeAgain]

When Eugene Stoner designed the AR-15, he had a "wish list" by the military that he had to accomplish. And somehow he did it.
Granted the original M16 had some minor issues, but all were quickly rectified with the A1 version.
I was issued the A1 and it served me VERY well.
There were a few changes with the A2 that I'd consider "improvements", but beyond those, I feel most were mistakes.
The pistol grip feels better, the 3 round burst makes sense (but they should have had a 4 position selector for full auto as well).
I'm not sure which version had the closed bottom, "bird cage" flash suppressor, but that was good too. Beyond that, I'm not at all impressed.
The only benefit I see to the round handguards is cost and supply.
The easily adjustable sights were a colossal mistake! At least for combat.
Adding to the errors, one of Stoner's biggest obstacles to overcome was weight. That was ignored with the A2 and subsequent versions. And it's getting worse!
I've seen some civilian versions with so much "junk" added on, it looks like something Inspector Gadget would carry into battle.
Short of buying something used or building from scratch, one would be hard pressed to find a "normal" rifle or carbine on the retail market.
Back to full auto Vs burst. I wouldn't dare say full auto isn't fun but there are very few situations where it's practical. In combat, with limited supply, the burst makes more sense. Either way, unless absolutely necessary, both are a waste of ammo.
I'm interested in hearing the logic behind changing Stoner's design after the M16a1 and closely related carbines.
Believe it or not, I'm interested in other's opinions.

 

[herrwalther]

The pistol grip feels better, the 3 round burst makes sense (but they should have had a 4 position selector for full auto as well).

That would have been interesting. Speaking from a training perspective, would be hard to teach PVT Snuffy on it. A 90 degree turn on a 3 position SAFE-SEMI-BURST/AUTO, was easier to point out. I have trained on HK service weapons that had 4 position selectors, and they took a much finer thumb movement to go from semi to burst instead of full auto or burst to semi instead of safe.

I'm not sure which version had the closed bottom, "bird cage" flash suppressor, but that was good too. Beyond that, I'm not at all impressed.

I believe that was the M16A2. The closed bottom compensator was vented at the top to compensate for muzzle rise but the closed bottom helped reduce dust kick up when shooting in the prone. In theory this helped "hide" the shooter better. And also helped keep dust from flying in your face.

The easily adjustable sights were a colossal mistake! At least for combat.

I don't. The sights were easy to adjust in the field but not easy enough to bump off your sight zero. I liked them for what they were. Could they have been better? Sure. But by the time I knew better we had red dot sights on the M4 or M4A1.

I was issued the M16A2 first. Then went to the A4. Somehow I skipped right over the A3. And I don't think I ever saw them. Then I had the M4 and M4A1 back and forth. On deployment I had both an M4 and M16A4. Thankfully, only had to carry one at a time. Mostly. I had no major problems with the rifle while in service.

 

[shoobe01]

Eugene Stoner didn't design the AR15.

He did the AR10.

Jim Sullivan did the AR15 (with a small team). He designed a bunch of things, but mostly was an expert at shrinking down stuff, and making clever ideas more suitable for mass production, longevity, etc.

Most recently worked on the Surefire quad-stack mags. He also designed the Ultimax (!). He also worked on the Ruger M77 rifle, Stoner 63 (largely by being the guy to scale down the Stoner 62), and Ruger Mini-14 (Again... scale down properly to make not just function but easier to make, fix problems, etc). And a 7.62 chain gun for Hughes and so on. And several not launched programs including the Surefire MGX, something in Italy which I presume is the Franchi 641, and more.

There's some good videos of him being interviewed and test firing with Gun Jesus and more but this excerpt from a written interview about the AR15 may be of interest.

Sullivan: From the start, we (Bob Fremont and I) put the AR-15 gas tube on top and used the AR-10-type cocking handle on the first prototypes. But the Finger hook of that type of cocking handle has to have an open slot in the top of the receiver which weakens it and since the hot gas tube was now just below the hook, the hook got so hot on full auto it burned your finger when trying to cock. So I redesigned the cocking handle to pull from the rear which doesn’t get hot and that allowed the receiver slot to be closed off so the AR-15’s receiver became stronger than the AR-10’s.

Although the two guns generally look the same, most of the details in the AR-15 differ from similar details in the AR-10 in ways that made the AR-15 parts more readily interchangeable, simpler and cheaper to make, easier to takedown, smoother operation, stronger, and with increased spring room which made the AR-15 more reliable and eliminated the need to replace springs that could set.

We designed the cartridge for IMR tubular grain powder instead of Winchester’s Ball powder and contracted with Remington to make the ammo. We therefore developed the gun and gas system for the pressure curve of IMR powder and other characteristics of that ammo.

Unlike the AR-10, which had only marginal room for its extractor spring, the relatively larger bolt of the AR-15 had adequate spring room to operate reliably with our ammo. Although we made a modified bolt with even more room, it proved unnecessary during extensive test firing so we went into production with the apparently adequate and simpler design. That became a bad choice later.

We made three other bad choices - the cartridge rim should have been thicker and/or stronger, the buffer should have been heavier, and the chamber of the barrel should have been chrome plated. Omitting the chamber chrome plating was outright stupid but none of the “bad choices” caused problems during our tests or the Army’s tests of the first Colt production guns or the first combat reports from Special Forces in Vietnam, which said that the AR-15 and cartridge were absolutely deadly and effective and superior to the Army’s .30 cal. M-14. By 1962, the world’s press was calling the AR-15 a miracle or “Super Gun,” but that didn’t last long.​

https://www.smallarmsreview.com/display.article.cfm?idarticles=2772

A lot of the later work was done by Colt in house designers at the behest of the Army, after Armalite sold the design, so yet another set of people were responsible for that, and often being a team there's no one clear documented reason any very specific design choice happened.

 

[CapnMac]

The only benefit I see to the round handguards is cost and supply.

The rounds will not pinch your palm if the get out of alignment. And the heat deflectors seem to work better, for not having any potential gap being in an inconvenient vertical plane.

Turning the beast into an 8# target rifle from a 6# service rifle is just what it is.

 

[citizenconn]

The rounds will not pinch your palm if the get out of alignment. And the heat deflectors seem to work better, for not having any potential gap being in an inconvenient vertical plane.

Plus each half is interchangeable on the rounded handguard whereas the triangular one is two distinct units, requiring two part numbers rather than one interchangeable one. Much better logistically.

 

[SmeeAgain]

I don't. The sights were easy to adjust in the field but not easy enough to bump off your sight zero. I liked them for what they were. Could they have been better? Sure. But by the time I knew better we had red dot sights on the M4 or M4A1.

I was issued the M16A2 first. Then went to the A4. Somehow I skipped right over the A3. And I don't think I ever saw them. Then I had the M4 and M4A1 back and forth. On deployment I had both an M4 and M16A4. Thankfully, only had to carry one at a time. Mostly. I had no major problems with the rifle while in service.

There was a very valid reason for the A1 sight design. (Requiring a bullet or tool to adjust the sights.) That was "nervous fingers and combat are a dangerous combination". Meaning that once a rifle is changed from "zero", it is difficult if not impossible to reestablish it in the jungle. "Zero" is best set under ideal conditions like on a range. Logic suggests that windage / elevation variants are best compensated (under constantly varying conditions) by estimation with the sights remaining at zero as conditions will likely change seconds later. Adjustable sights are great for your hunting rifle but a really bad idea for jungle warfare.

 

[SmeeAgain]

Eugene Stoner didn't design the AR15.

He did the AR10.

Jim Sullivan did the AR15 (with a small team). He designed a bunch of things, but mostly was an expert at shrinking down stuff, and making clever ideas more suitable for mass production, longevity, etc.

Most recently worked on the Surefire quad-stack mags. He also designed the Ultimax (!). He also worked on the Ruger M77 rifle, Stoner 63 (largely by being the guy to scale down the Stoner 62), and Ruger Mini-14 (Again... scale down properly to make not just function but easier to make, fix problems, etc). And a 7.62 chain gun for Hughes and so on. And several not launched programs including the Surefire MGX, something in Italy which I presume is the Franchi 641, and more.

There's some good videos of him being interviewed and test firing with Gun Jesus and more but this excerpt from a written interview about the AR15 may be of interest.

Sullivan: From the start, we (Bob Fremont and I) put the AR-15 gas tube on top and used the AR-10-type cocking handle on the first prototypes. But the Finger hook of that type of cocking handle has to have an open slot in the top of the receiver which weakens it and since the hot gas tube was now just below the hook, the hook got so hot on full auto it burned your finger when trying to cock. So I redesigned the cocking handle to pull from the rear which doesn’t get hot and that allowed the receiver slot to be closed off so the AR-15’s receiver became stronger than the AR-10’s.

Although the two guns generally look the same, most of the details in the AR-15 differ from similar details in the AR-10 in ways that made the AR-15 parts more readily interchangeable, simpler and cheaper to make, easier to takedown, smoother operation, stronger, and with increased spring room which made the AR-15 more reliable and eliminated the need to replace springs that could set.

We designed the cartridge for IMR tubular grain powder instead of Winchester’s Ball powder and contracted with Remington to make the ammo. We therefore developed the gun and gas system for the pressure curve of IMR powder and other characteristics of that ammo.

Unlike the AR-10, which had only marginal room for its extractor spring, the relatively larger bolt of the AR-15 had adequate spring room to operate reliably with our ammo. Although we made a modified bolt with even more room, it proved unnecessary during extensive test firing so we went into production with the apparently adequate and simpler design. That became a bad choice later.

We made three other bad choices - the cartridge rim should have been thicker and/or stronger, the buffer should have been heavier, and the chamber of the barrel should have been chrome plated. Omitting the chamber chrome plating was outright stupid but none of the “bad choices” caused problems during our tests or the Army’s tests of the first Colt production guns or the first combat reports from Special Forces in Vietnam, which said that the AR-15 and cartridge were absolutely deadly and effective and superior to the Army’s .30 cal. M-14. By 1962, the world’s press was calling the AR-15 a miracle or “Super Gun,” but that didn’t last long.​

https://www.smallarmsreview.com/display.article.cfm?idarticles=2772

A lot of the later work was done by Colt in house designers at the behest of the Army, after Armalite sold the design, so yet another set of people were responsible for that, and often being a team there's no one clear documented reason any very specific design choice happened.

I'm not sure how or where that myth got started but Stoner was the #1 man throughout the entire ordeal. Sullivan and others were subordinates working on specific areas under Stoner's leadership / control.
Like many others, the AR-15 is credited to Eugene Stoner for good reason.
To dispute that is like Al Gore saying he invented the Internet.

 

[12Bravo20]

There are more positive things about the A2. As mentioned the round hand guards are better. The Bruton Bump (brass deflector) is a definite plus for us left hand shooters. The heavier A2 barrel doesn't heat up as quick and cause POI to wander like the A1. And I for one think the A2 sights are an improvement over the A1 sights. Yes I have used the elevation as designed to hit targets past 300 meters, it works as intended. I also don't find the rear windage adjustment easy to bump. And we were all taught not to mess with the windage once we zeroed our rifles.

The downside to the A2 is the trigger pull. The 3 round burst cam makes the trigger pull heavier than the full auto trigger on the A1.

As far as the A3 and A4 goes, the only difference is that the A3 is full auto while the A4 is burst.

 

[SmeeAgain]

There are more positive things about the A2. As mentioned the round hand guards are better. The Bruton Bump (brass deflector) is a definite plus for us left hand shooters. The heavier A2 barrel doesn't heat up as quick and cause POI to wander like the A1. And I for one think the A2 sights are an improvement over the A1 sights. Yes I have used the elevation as designed to hit targets past 300 meters, it works as intended. I also don't find the rear windage adjustment easy to bump. And we were all taught not to mess with the windage once we zeroed our rifles.

The downside to the A2 is the trigger pull. The 3 round burst cam makes the trigger pull heavier than the full auto trigger on the A1.

As far as the A3 and A4 goes, the only difference is that the A3 is full auto while the A4 is burst.

I gotta admit, you made sense on every point. Starting with the handguard thing... When I held the M16a1 for the first time (which was also the first time seeing one) it looked and felt like it came from another planet. I wasn't fond of it at all. After shouldering and shooting it I thought "Hey, maybe this could work." The more familiar I became with it, the more I liked it. Seems we all prefer what we were issued. Being older than dirt I "prefer" the triangular handguards. But admittedly, I've never given the round ones a fair chance. Manufacturing & logistics are definitely better. I've paid close attention to the brass deflector and they do seem to stack brass in a tidy pile where the A1 throws cases everywhere. So yeah, that's an improvement too. I was long gone when the A2 and subsequent versions appeared so I've never had the opportunity to fire a "burst". But it is completely logical. It's extremely rare to need full auto, and your finger could easily compensate with the burst mode. In a combat situation ammo may become scarce. Conservation is paramount! As I said previously, that's a huge improvement. As for the heavy barrel, I'm still not convinced the added weight is worth it. While it may take longer to heat up, it also takes longer to cool! One could become quickly dehydrated using bodily fluids to cool an overheated weapon.
One thing that hasn't come up yet is buttstock length. The first versions were substantially shorter than the A2. I'm trying my best to avoid sounding racist but our South Vietnamese partners couldn't handle the longer rifles. I saw plenty with American issued M1 / M2 carbines & M16s but never an M14. They were simply too long & heavy for them. Once we were out of S.E. Asia, the stocks were lengthened to accommodate larger American frames.

 

[CapnMac]

the stocks were lengthened to accommodate larger American frames.

Which became more complicated when we started wearing armor and plate carriers with/as LBE. Suddenly, things wanted to be shorter, enter the M4 adjustable stock.

 

[mokin]

I was issued an M-16A1 in Boot Camp then an A2 when I got to the fleet. Other than the closed bottom on the flash suppresser, I preferred the A1. I did not notice the difference in the stock length, the triangular handguards seemed easier to hold, and although the rear sight on the A2 was easier to adjust, it seemed like a whole lotta moving parts. I have mixed feelings about the trigger. While the burst feature changed the pull, I doubt most guys were aware enough to tell a difference.

 

[entropy]

The only thing the A1 had over the A2 ( I fired, qualified, and worked on both) was the Safe/Semi/Auto FCG. The 3 rd. burst muddled up the trigger on the A2. In every other aspect it was far superior from a rifleman's viewpoint.

 

[Slamfire]

Eugene Stoner didn't design the AR15.

He did the AR10.

Jim Sullivan did the AR15 (with a small team). He designed a bunch of things, but mostly was an expert at shrinking down stuff, and making clever ideas more suitable for mass production, longevity, etc.

Most recently worked on the Surefire quad-stack mags. He also designed the Ultimax (!). He also worked on the Ruger M77 rifle, Stoner 63 (largely by being the guy to scale down the Stoner 62), and Ruger Mini-14 (Again... scale down properly to make not just function but easier to make, fix problems, etc). And a 7.62 chain gun for Hughes and so on. And several not launched programs including the Surefire MGX, something in Italy which I presume is the Franchi 641, and more.

Very interesting. People want simple, straight forward creation myths, and they want a big man, a Titan, standing on Mount Olympus, moving the world all by himself. They don't want to know that design is a team effort, and that there are a huge number of people involved in modern projects. Nope, they want that guy with a hammer, pounding a red hot on an anvil, shaping it all by himself to be a rifle, an airplane, or an air craft carrier. People want a hero.

 

[CapnMac]

and they want a big man, a Titan, standing on Mount Olympus, moving the world all by himself. They don't want to know that design is a team effort, and that there are a huge number of people involved in modern projects.

True. Mikhail Timofeyevich Kalashnikov had a large team working a long time to finally get the stamped version of the AK-47 out the door. The Kalashnikov Design Bureau employed a few thousand people.

 

[twarr1]

I was issued the short-lived M16A1E1. It had the closed bottom compensator.

 

[entropy]

True. Mikhail Timofeyevich Kalashnikov had a large team working a long time to finally get the stamped version of the AK-47 out the door. The Kalashnikov Design Bureau employed a few thousand people.

And they borrowed heavily from the StG44.