M4 and reliability: Debunking the piston myth

[thesheepdog]

I have to go but:

1. I've shot Mini-14(old versions). AR system does get dirtier/hotter in chamber due to gas impingement.

Problem with old Mini-14(lack of accuracy) has more to do with manufacturing/quality control than gas piston system.

2. you want to keep gas/powder residue separate from chamber since more fouling/heat in the chamber will increase rate of tear and wear.

Again, you have to make sure that all other factors, including quality of components, are same.

3. turbo charging on cars: if both cars have turbo charging and are same in all other aspect, then the one with cooler/cleaner engine will last longer.


4. I think you misunderstand again. The problem is not hot gas/powder residue cleaning the chamber but

i. making it more dirty(gas coming in carries with it more dirt and hot air as well)
ii. increasing heat which will raise rate of tear and wear

Put it to rest will you? I know more about heat on metal than most people do. I am a welder/fabricator and can tell you that you don't need super strength (titanium-carbon fiber-diamond-coated) materials for a firearm. Steel is extremely tough. Don't believe me; try building stuff out of it for 5 years, then tell me how you feel. Even cutting torches don't put a dent on steel sometimes.

.22lr is right. I would suggest listening to that type of advice since I can't seem to get the point across to you.

 

[Bartholomew Roberts]

You can find web links/posts to support anything, from curing cancer by diet to making phenomenal returns based on pyramid schemes.

Then it shouldn't be especially burdensome to provide the links that support your point of view, since I am pretty sure your opinions aren't based on first hand experience.

Furthermore, not everything in this world is duplicated in web space(that's why we still have printed publication).

That's fine. If you've got a publication that informed your opinion, I would love to hear about it. I already know your opinion though - restating it a dozen times in a dozen different ways doesn't do anything to convince me.

Here are the facts about gas impingement system:
- it gets dirtier compared to gas piston system(increased rate of fouling)
- the system runs hotter

Assuming you are talking about the chamber/bolt (since gas pistons don't magically dispel heat or fouling but merely shift it to different places), how much dirtier and how much hotter?

In the few tests I've seen that attempt to qualify this, the answer is tthe chamber and bolt doesn't get that much hotter and or that much dirtier. The primary place fouling collects on an AR bolt is the tail - and if you know of any failures due to fouling of the bolt tail, I'd sure love to hear about it since that is a new one to me.

Basic engineering principle: a system which runs hotter and suffers from increased rate of fouling also suffers from decreased durability and reliability.

As pointed out earlier, piston rifles simply shift heat and fouling to a different location. They aren't any cooler or cleaner.

If you don't believe any of this, don't change the oil in your car and see how well it functions.

How about instead of using any one of your analogies, I just take an AR rifle and shoot it without cleaning for thousands and thousands of rounds - not only will the results be more relevant; but I'm already doing that anyway so it won't require much effort on my part. When I have a problem with my "unreliable" AR, I'll let you know. While we're waiting, you can take a look at these other people doing the same thing:

Unless DC Capitol Police changed to M4 because G36 was UNRELIABLE and M4 WAS RELIABLE, it doesn't have any relevance.

So if your receiver warps due to heat and shifts your point of impact a foot to the right, that isn't relevant because the important thing is that the gun went bang?

according to IDF, IDF chose Tavor over M4/M16 in field trial because Tavor showed increased, not less or equal, reliability when compared to M4/M16 that they get for very little money(Tavor cost them much more since they don't get it in foreign assistance like M4/M16).

Here is a discussion from soldiers in the Givati Brigade. It appears the Tavor is getting a mixed reaction at best. For example, until the most recent generation of Tavor, the commander of the Givati Brigade ordered troops to continue using the M16 because of "jamming" issues with the Tavor.

Financial incentive for IDF is to stick with M4/M16 platform since they can get it for little or no money from US, not switch over to Tavor.

Israel has already sold the Tavor to Columbia, Georgia and India and the Israeli defense industry relies on foreign military sales. Wonder how many Tavor's you have to sell before it becomes cheaper than buying subsidized rifles from another country? It would seem to me that financial incentives could go either way.

My bet is that Capt. Self's M4 was rebuilt so much that it was essentially a NEW gun.

Instead of making bets you would lose, you could just read the link I provided earlier. But what did you want to bet? I'll take free money.

And while you are repeating "engineering and design" like Rainman before the People's Court is on, have you considered that most machines are compromises? For example, while I might very much like a rifle that has a service life of 50,000 rounds and can be fired 10,000 rounds between cleanings, I might prefer a rifle that weighed 2lbs less and only had a service life of 40,000 rounds and 2,000 rounds between cleanings.

Please note: I haven't stated a preference of Direct Impingement vice Piston. It really doesn't matter in the grand scheme of things! Learning to use and maintain your chosen weapon system well does!

Heresy! Burn the witch! Next you'll tell me that discussing how many angels can dance on the head of a pin serves no practical purpose.

 

[.22lr]

Heresy! Burn the witch! Next you'll tell me that discussing how many angels can dance on the head of a pin serves no practical purpose.

OF COURSE the number of angels doesn't matter! Its all in the choreography!

 

[Slamfire]

Wonder how many Tavor's you have to sell before it becomes cheaper than buying subsidized rifles from another country?

Buying subsidized rifles? Those M16's are foreign aid. They are free. You can't get cheaper than free.

We are giving Israeli direct military aid of $3.0 Billion a year. What we give in terms of other aid I don’t know. But it works out to $400.00 per Israeli pre year in military aid. And they don’t exactly have to buy new rifles each year.

Seems to me, use free American rifles and sell good Tavors for a profit is a smart business decision.

Who exactly is buying M16's? What Nations are buying M16's from us? Don't we have to give them away?

And while you are repeating "engineering and design" like Rainman before the People's Court is on, have you considered that most machines are compromises? For example, while I might very much like a rifle that has a service life of 50,000 rounds and can be fired 10,000 rounds between cleanings, I might prefer a rifle that weighed 2lbs less and only had a service life of 40,000 rounds and 2,000 rounds between cleanings.

The AK47 was chosen after extensive competitions against other designs. After the “best” design was chosen, the AK47 underwent years of refinement before it was issued to troops. The AK47 has a reputation of outstanding reliability.

The M16 was not chosen after competition against other designs. It was chosen by Gen Curtis Le May after a watermelon shoot. The M16 never had any prior period of refinement before it was issued. Soldiers had to die before any fixes were implemented in the design. Those design changes could not violate the form/fit of the basic design, so there was very little wriggle room for improvement of a fundamentally flawed design. Today, almost 50 years after this rifle was issued, it still has magazine problems.

4. assertion that M4/M16 is super durable/reliable because samples from 1960s still exist today and works, and is being used by people such as Montagnards

I really doubt there are any early M16’s in service. They were junk.

From the book "The Gun" the first M16's literally were rusting away in theater. Colt had not considered corrosion control in the design of the rifle. The book says these rifles were literally rusting away in the hands of the troops. In the early 80’s I saw a table full of M16 parts as a part of a display by a corrosion control expert. These were M16’s that had severe pitting as a result of exposure, in Vietnam, I think. I remember picking up uppers that the pitting was almost through the metal. The ones that were not strong enough to survive handling had been tossed out years before.

A bud of mine who works at Anniston Army Depot told me of very early M16’s that came in when he worked on the line. There is stuff that comes out of Armories and storage locations that get sent to Anniston Army Depot all the time. I remember him describing something special about the flash suppressor. He knew they were rare and historic, but they went into the shredder with all the other obsolete trash.

I am therefore of the opinion that if any of those early model M16’s surface within the military inventory, they are sent to Anniston Army Depot and are converted into good scrap metal because the military understands they were and are, POS.

 

[HorseSoldier]

Financial incentive for IDF is to stick with M4/M16 platform since they can get it for little or no money from US, not switch over to Tavor.

It's not really that clear cut. The Israelis previously fielded the Galil, another (sort of) home grown design, and previously got AR type weapons for cheap going back as far as M16A1s in the '73 war. Super reliable AK style piston rifle versus the dreaded DI gas M16 . . . and the IDF issued the M16s, M4s and 177s to their actual shooters and kept the Galils for issue as secondary weapons to guys who needed a PDW like tank and artillery crews.

In other words, procurement of ARs by the IDF may be financially motivated, but their decision to make it their primary fighting rifle/carbine rather than an AK-piston design reflects the reality that the AR gets the job done just fine.

it's the purpose of military, for the sake of morale, to always train soldiers so that they would have utmost confidence in their weapons, whether justified or not.

I wouldn't place too much weight on soldiers' confidence being reflective of weapons' reliability.

If the DI is doing his duty, then even soldiers armed with single shot rifles should have confidence, LOL.

You should perhaps take a better look at the conversation -- both the author in the original referenced article and several of the US military folks posting in this thread have extensive training on foreign weapons systems as well as USGI stuff. Saying an SF team sergeant has been brainwashed by a drill sergeant to repeat by rote propaganda about the M16/M4 is untenable.

 

[thesheepdog]

Today, almost 50 years after this rifle was issued, it still has magazine problems.

That's not the gun's fault. PMAG has revolutionized the AR mag to extremely high ratings among military and civilians. But the military doesn't think firearms maintenance is necessary anymore; because most warfare is becoming less and less involved with the individual grunt (Predator missles, XM-25, Snipers, etc)

I don't think you should be blaming the AR/M16 design for deaths of US soldiers. Soldiers are going to die in combat whether you like it or not. It's part of war.
There's more to it than that. If proper ammo isn't used, the rifle won't function; if proper training isn't given to fire the weapon, and maintain it, the troops will be rendered ineffective with it; if the military superiors can't provide you with proper maintenance supplies, your gun will fail.

You can say the same thing about any piece of machinery that exists on this planet.

 

[Brenten]

gas piston system last longer because it's runs cooler and cleaner, for the same reason your car engine lasts longer if it runs cooler and cleaner.

Right Stick your hands where the gas port on a piston gun is and tell me it is cool. Unless you have some magic dust, the heat is still there, just in a different place. In a piston gun the HEAT is at the center of a barrel. How many bent AK barrels have you seen? I have seen many. At first I thought it was from bozo's using them as prybars. Later on I found out that the heat cycling of the barrel softened it up in the center and caused the steel to weaken. Metal bends very well when the heat is applied to a specific area.

Cleaner? ever so slightly and definitely not worth the extra mass of moving parts and the extra parts themselves. After 500 rounds in each gun, I could not tell the difference. The bolt face and the chamber was cruddy in all my weapons using wolf ammo. Gas gets around the bolt during firing and this causes nearly as much fouling. Hell, it almost seemed to me that the sig was chucking more crud out during firing than my m4.

DI: Less moving parts to break. Much simpler system overall. Less mass moving back and forth during operation means less wear and tear on frame and components. No recoil spring above barrel to get thermally cycled and fail. No heat centered on barrel to thermally cycle barrel and weaken steel. DI is newer, piston has been around forever.

Less moving mass also means better accuracy, undeniably.

Piston has no standardization of design, they are all different. Gas tubes are gas tubes, simple and effective.

again piston is not a solution but an alternative.

 

[HorseSoldier]

Who exactly is buying M16's? What Nations are buying M16's from us? Don't we have to give them away?

Variations on the M4A1 is basically the industry standard for special operations forces in nations that don't have exclusive marketing relationships with HK. Australian SASR and their commando-role infantry guys use M4s instead of the AUG. UK SAS uses them instead of HK revamped L85A2s. Colombian SOF uses them instead of Galils or Tavors. Etc.

 

[Brenten]

It's not really that clear cut. The Israelis previously fielded the Galil, another (sort of) home grown design, and previously got AR type weapons for cheap going back as far as M16A1s in the '73 war. Super reliable AK style piston rifle versus the dreaded DI gas M16 . . . and the IDF issued the M16s, M4s and 177s to their actual shooters and kept the Galils for issue as secondary weapons to guys who needed a PDW like tank and artillery crews.

In other words, procurement of ARs by the IDF may be financially motivated, but their decision to make it their primary fighting rifle/carbine rather than an AK-piston design reflects the reality that the AR gets the job done just fine.

exactly
If money was such an issue for the IDF, then I guess all those DI SR-25's would not have been purchased by them you could pay for 2-3 piston guns with each SR-25. with the IDF and the Israelis in general it was never about the money because if you knew how much they get from the US annually in funding you'd realize the rifle fund is a drop in the bucket.

 

[LinuxHack3r]

Not going to go into detail and repeat everything that has EVER been said about Piston vs. DI. However, count me in this group:

DI is perfectly fine.

Some weapon designs that are based on pistons work great.
IMHO the AR/M16/M4 platform also works great.

 

[Brenten]

Who exactly is buying M16's? What Nations are buying M16's from us? Don't we have to give them away?

Can they give them away to me for personal keepsake?

15 NATO countries and:

# Afghanistan
# Australia
# Bangladesh
# Barbados
# Belize
# Bolivia
# Bosni
# Brazil
# Brunei
# Cambodia
# Cameroon
# Canada:
# Chile
# Costa Rica
# Democratic Republic of the Congo
# Denmark
# Dominican Republic
# East Timor
# Ecuador
# El Salvador
# Estonia
# Eritrea
# Fiji
# France
# Gabon
# Ghana
# Greece
# Grenada
# Guatemala
# Haiti
# Hondura
# India
# Indonesia
# Iraq: Iraqi army
# Israel
# Jamaica
# Jordan
# Lebanon
# Lesotho
# Liberia
# Lithuania
# Malaysia
# Mexico
# Monaco
# Morocco
# New Zealand
# Nepal
# Netherlands
# Nicaragua
# Nigeria
# Oman
# Pakistan
# Panama
# Peru
# Philippines
# Qatar
# Senega
# Singapore:
# Somalia
# South Africa
# South Korea
# Sri Lanka
# Thailand
# Tunisia
# Turkey
# Uganda
# United Arab Emirates
# United Kingdom: Special Air Service
# United States
# Uruguay
# Vietnam

 

[KChen986]

...

 

[Brenten]

Whatever works is fine. like this

http://www.popsci.com/technology/ar...carry-laser-guided-smart-bullet-weapon-battle

 

[Quentin2]

-Pick a weapon
-Learn the weapon
-Maintain the weapon
-STOP WORRYING!

I agree with .22LR, choose your weapons, shoot them and stop worrying so much about what I picked - which happens to be a quality DI AR.

We all must do our research and choose what we believe will do the job. If it doesn't do the job, more research is in order. Mine works so I'm not ready to dump it for "new and improved". If yours works, good for you!

 

[radom]

Just keep in mind that the fix for the M-16 issue was the gas piston AR-18. It was a huge flop due to the gas piston not being as reliable as the M-16 system.

Another point is the M-16 has around 1/4 the fail to fire falure rate as the M-1 "the best battle implment invented by man".

 

[tirod]

I suspect the M16 has a lower failure rate is because the action is almost totally enclosed and protected. M1? Exposed top eject bolt and exposed fixed handle reciprocating operating rod. It's just as well there are only 5,000 of those rebuilt M14's going into Afghanistan, it's going to take a lot of work to keep them running. They have a higher failure rate because they aren't as well designed to protect the action. Just one more reason they became obsolete 45 years ago.

Temps? If it was a concern, a little surfing on the web would pick up threads this year on AR owners using infra red reading sensors to evaluate a number of different firearms. A general summary is that the DI system AR bolt reads about 30 degrees warmer than a piston bolt, and the the AR and piston barrel both get hot.

Look further and you see the AR carrier not getting as hot as the piston chamber on the barrel. They are doing the same thing, exposed to the same gas, and all that's different is that the piston in the AR is the back of the bolt - and it counteracts the chamber pressure just when it needs to.

Either way, once extraction starts, BOTH have barrel gas flowing past the brass and into the action. ALL self loading actions do that, including blowback and roller locked.

I had a HK91, I could fire a mag of twenty rounds and it got plenty dirty. It has no other source of gas residue other than the barrel itself, and the obvious conclusion is that gas residue in the barrel is a significant source of action contamination. Again, all self loading actions suffer this regardless of whether they are gas operated or how.

Since the AR ports gas through the gas key into the carrier, pressurizing it, the assembly then expands and uncovers the two gas aperatures on the side of the carrier, releasing it out the ejection port when open, which is most of the time. So, the gas residue isn't getting into the "action" any more than a gas piston setup on the barrel.

The failure in analysis is assuming where the gas is coming from, and in the AR, most critics don't have a clue, don't really examine the gas path, and don't have comprehensive comparisons to a control weapon - like the HK.

They simply repeat unfounded anecdotal gunstore BS. The average American is a technical ignoramus, just hang around an auto parts store on a Saturday morning with someone who does know better, and they can explain it with live examples.

Here, we have to deal with the written word, but it doesn't mean it's any more informed. If anything, the propriety nature of firearms designs tends to restrict the information. Add a huge dose of testosterone, and a reasoned analysis tends to dissipate faster than gunsmoke.

DI is more efficient than piston, weighs less in execution, and works in the military environment where civilian guns would miserably fail. Let's not advocate a return to the uninformed fantasy of olden days, old fashioned actions, and even worse, throw away what they worked so hard to make obsolete.

 

[stellite]

http://www.youtube.com/watch?v=CqRwx4wtmms&feature=related



LOL

http://www.youtube.com/watch?v=X7IGHWIMNE0&feature=related

 

[Slamfire]

I don't think you should be blaming the AR/M16 design for deaths of US soldiers. Soldiers are going to die in combat whether you like it or not. It's part of war.

Lots of Soldiers died in Vietnam because their M16 jammed. The rifle was not ready for prime time.

The US Army covered it up until it too many letters to Congressmen and Newpapers forced them to acknowledge there was a problem.

Putting profits above the lives of American Soliders is obscene.

It should not be a "part of war", but it is, and I don't like it.

 

[notamisfit6]

Lots of Soldiers died in Vietnam because their M16 jammed. The rifle was not ready for prime time.

The RIFLE wasn't ready, or the incompetence/deliberate sabotage of the Army Ordinance Board made it unready?

Besides that, how does the performance of rifles 40 years ago, firing corrosive, dirty ammo out of its pressure curve, with no chrome protection to the bore or chamber pertain to the DI vs piston debate today?

 

[thesheepdog]

Lots of Soldiers died in Vietnam because their M16 jammed. The rifle was not ready for prime time.

Because:
Soldiers were not trained well on how to use it.
The ammo was corrosive.
Barrels and other parts were not chrome lined.

I wonder if you have any actual statistics on this, or do you just believe everything you read, write, hear?