The outdated M4 carbine and M-16 why is our military still using them?

Six years military experience three deployments and thousands of rounds put through an M4 Carbine, I truly do not understand why our military i.e. combat arms is still using that direct impingement piece of crap. Our main military rivals have been using piston driven rifles since the 1960’s, the primary example being the AK-47. Also the 5.56x45 round used in the AR-15 variety rifles is a joke in and of its self, requiring that our soldiers be trained to fire in controlled pairs so as to ensure enough damage is done the target because one round falls short a high percentage of the time. Now 5.56x45 has its positives it’s a low recoil round coupled with high velocity making it very controllable and easy to shoot, also it’s a small light weight round allowing for a high ammo capacity with the average combat arms load out. The kinetic energy of the round is pathetic carrying almost no punch behind it while at the same time its high velocity gives the round a tendency to pass through the target causing minimal damage hence the controlled pairs. Compared to the 7.62x39 the 5.56 is a varmint round, the 7.62 is designed to cause maximum damage to soft tissue, it’s a heavy slow moving round making it very very effective at stopping human targets.

Its disgusting really when you think about our troops in Vietnam fighting with AR-15’s in jungle conditions that direct impingement gas system in jungle conditions firing the light weight 5.56x45 through the jungle bush, in fire fights against the Vietcong’s piston driven AK-47 firing heavy devastating rounds ripping trough the bush. They didn’t stand a chance its almost like they set them up for failure, the M-14’s our troops started with were the way to go.

Keep your rifle clean and she will give you no trouble our team leaders said on my first deployment, bull#. In desert conditions it is near impossible to keep your rifle clean to standards , especially in Afghanistan with its silt like sand covering most of the country this is not normal sand I’m talking about this is something more akin to powdered sugar mixed with sand, god forbid it rains because this stuff mixed with water is something beyond mud. The more you oil your rifle the more this silt binds to the internals causing failures. Iraq presents the same issues with sand though its not quite as bad as Afghanistan, its flat land scape provides no cover from the winds or the sand storms coming with the winds.

Lets talk about the difference between Direct impingement and Piston operated, Both operate off the same principle of gas moving the bolt. The gas provided by the rounds fired in the rifle are funneled into the barrel part of the gas is diverted into a tube which leads back into the rifle moving the bolt and exchanging the round, the rest of the gas escapes through the end of the barrel . Now a piston system uses a rod attached to the bolt , the gas pushes the rod which in turn pushes the bolt the excess gas escapes back out of the piston, it’s a clean system no actual gas , carbon or powder is pushed into the bolt . A Direct impingement system on the other hand uses the gas itself pushed directly into the bolt to operate it, along with the gas comes carbon , powder , metal’s and other trash all pushed into the bolt compounded more and more with every round you fire building up in the bolt causing failures , now lets say you add oil to avoid jamming the bolt which will work at first, eventually it makes the situation much worse as the carbon, powder and other garbage is mixing with the oil creating a non-recoverable failure which can and will get you killed in the heat of a fire fight. The more rounds you put through an M-4 during a fire-fight the more likely she is to jam period no matter how well maintained the rifle is, An AK-47 or any piston driven rifle for that matter does not suffer this , just ad a little oil and that piston will just keep on stroking until you run out of ammo, 1 round or a 1,000 it makes no difference the gas and trash is not being pushed Into the bolt group in piston rifles. Piston rifles are far more balanced, each stroke of the piston is equal using the same amount of gas each time, DI on the other hand is chaotic at best blowing unmeasured amounts of gas round to round into the bolt group. This is why piston rifles are far more reliable and high performance with suppressors, as the piston can be manipulated to expel more gas making rounds being fired uniformly balanced low velocity across the board, DI rifles require low velocity rounds with suppressors and even then they shoot like complete garbage with suppressors fixed.


There are AR-15 type rifles on the market with piston systems, why in gods name are our troops not carrying these rifles. It would require very little retraining of our combat arms troops to switch over to a piston driven M4 / M16. And of course one more thing we need to switch to the 6.8spc , it is the most well balanced round on the market with out question.

Thank you for your time guys, I am new hear and I know I have not earned the respect of your time so I appreciate your time in advance.

a reply to: asabuvsobelow

In short, I would suggest it comes down to "economics". I am certain there are some very practical reasons as well.

a reply to: asabuvsobelow

Star and flag for you.

Our UK forces were using impractical rifles for years.

Like you say, the weapon needs to reflect the environment it's used in.

a reply to: asabuvsobelow

The Army has been attempting to replace the M16 for 50 years.

N ext Generation Squad Weapon

Piggy backing off of Zaphod. The Army has all the money for a large change like this.

When the Army moves on so will the Marines.

Another factor is weight on patrols.
5.56 you get about 37 rounds for every pound of ammo your carrying.

7.62 you're getting about 19 rounds per pound.

Why is our military still using them?

Because ... gurlz are weak.

a reply to: asabuvsobelow

Well written, thanks for the thread. I personally chose .30 cal. for my higher capacity semi auto rifle, with a piston system.

I cannot understand caliber anymore than piston vs. impingment, however you are right on the mark regarding the bolt and receiver getting terribly fouled with the latter.

Seems elementary to me.

a reply to: watchitburn

Great quote from a book I've read a number of times. "The US started going downhill when we switched from a round designed to kill our enemy to one designed to piss them off."

A dude I used to know was in Somalia (one of the dudes jumping off a little bird) when the poo hit the fan, said it was like shooting zombies and they wouldn’t go down, they kept coming, said the drugs the enemy was on was scary.

originally posted by: Zaphod58
a reply to: watchitburn

Great quote from a book I've read a number of times. "The US started going downhill when we switched from a round designed to kill our enemy to one designed to piss them off."

Expenditure of ammunition my DI called it in basic, we can always get more ammunition he said but we cant always get more soldiers. Fire superiority is what they teach to regular infantry put more rounds than the enemy and we win is the logic, accuracy takes a the back burner in the regular Army. Now when you move on up to JSOC / Ranger Battalion you are retrained and often refitted with FN Scars as well, but still using the 5.56x45 unfortunately . Its an easy to shoot round accurate and light weight end of story, logistically it makes since to the Army.

a reply to: asabuvsobelow

The 5.56 makes sense logistically, and for carry weight of troops, but it really does just piss people off when they're shot with it. Kind of like the 9mm used by base police. You can carry more rounds, but you need to put more rounds downrange too. So it's a trade off. Then again, the average infantry troop isn't an expert marksman, so they need more rounds to hit their target downrange.

Because when you retool the lower to only allow semi-auto, the M4 has the ability to destroy targets without an operator present. The military has known this for years, and this explains their silence, and even active resistance at times, toward efforts to outlaw assault weapons for civilians. Because that's what they are. They are weapons that assault people. Great for the military, bad news for John Q. Public. If it ever got out that we have semi-autonomous killing machines fighting our wars for us, well, say goodbye Defense budget.

If the 2nd amendment is so important, why is it only the second? Isn't second place first loser?

a reply to: Zaphod58

There is a book - MISFIRE by William Hallahan which details how Ordnance Bureau bureaucrats have for past 150 years screwed up rifle design and procurement

From not providing Union soldiers with breech loading and repeater firearms, which were available, to foisting such
kluges like Krag Jorgenson to bungling the M16 early in Vietnam

Reason was that giving troops rapid fire weapons would cause them to go wild and shoot off all their ammunition in one burst

www.amazon.com...

Kidding aside, I think it's because they're cheap, reasonably reliable, the infrastructure for cranking them out is well-established, and there's a long history of war profiteering in our country. Which isn't necessarily a bad thing, it only becomes one when you double deal, selling to both sides. I haven't seen evidence(yet) that we do that. It seems to me that we've spent a considerable amount of effort solidifying in the mind of the world that the M16 is America's rifle, and the M4 is America's carbine. I think this, in large part, is why you don't see soldiers of other nations carrying them. Not because they are superior or inferior, but because it's an American brand. It's a subconscious signalling that "nope, we keep our weapons to ourselves." Compare that with the ubiquity of the AK-47, and consider that in the context of the Cold War. Branding, marketing, public affairs: the hallmarks of capitalism.

Another consideration could be that should we arm our rank and file with state-of-the-art equipment, the same rank and file that very rarely encounter a firefight, it presents a risk of handing that equipment over to the enemy, should we lose that skirmish. I think the M4-M16 are closely balanced with the AK-47, so killing Americans to get their weapons isn't as much of a high-value target. Any more than it already is, that is to say. Better to take them alive, then use them for propaganda. I had to edit that last sentence. It was pretty gruesome before.

Talk is talk....but superior numbers managed responsibly always win....its easy to BS but if you were peppered with 2-3 of those Itsy-bitsy wee little rounds everyone is running into the ground I HIGHLY DOUBT YOU ARE FIELD FUNCTIONAL ANY LONGER and if you are give it 60 seconds your central nervous system will buckle.

Its like saying a >22 caliber bullet is useless....but if you had a couple zinging round and round in your skull making pudding you wouldn't underestimate the round or its lethality....sometimes overcompensating leads to careless perspectives habits and tactics....you don't normally use a sledgehammer to kill an ant...however if its all you have to weild...lol...have at er.

Many a hunter has used a.22 to kill Moose for sustinence...letting it slowly bleed out....quite effectively I might add....a World Record grizzly Bear was killed by a Woman who was Squirrel Hunting and berry picking using a single-shot .22 caliber rifle.

Those smaller rounds may not have been immediatly lethal but with a longer term perspective they put massive logistical material and manpower strains on your enemys….maybe I don't drop 100 of your men on the spot but I send 200 back to you wounded many terminally.....what impacts you the most expeditiously?....just saying.

I served 12 years including 2 tours in Afghanistan and 1 tour in Iraq with the 82nd. I had no complaints with my m4 carbine or the HK416. Just my .02.

originally posted by: asabuvsobelow


Its disgusting really when you think about our troops in Vietnam fighting with AR-15’s in jungle conditions that direct impingement gas system in jungle conditions firing the light weight 5.56x45 through the jungle bush, in fire fights against the Vietcong’s piston driven AK-47 firing heavy devastating rounds ripping trough the bush. They didn’t stand a chance its almost like they set them up for failure, the M-14’s our troops started with were the way to go.

Over one million North Vietnamese died compared to less than 50k Americans. Not sure where you get your information but being hit by a 7.62 or a 5.56 takes you out of a firefight. There is nothing wrong with the M4 or the 5.56 round for combat.

Just so you know, the M16/M4 isn't a DI system either. It's a modified verison. Also, the Piston driven rifles like the SCAR, XM8, AUG, G36, ARX160 are wider, weigh more, and have more moving parts that result in more issues than the m4. For someone that has been to the sandbox, you should know all this.

AK is garbage. Very inaccurate. M4 is accurate super versatile. Can be used long range, close quarters, ability to modify with scopes, grenade launchers. I retired with 20 years. I know that weapon like the back of my hand. It's a great general purpose weapon. Anybody who thinks an AK is better does not know weapons. It's more powerful but that's about the extent of it.

For the same reasons the AF flies 60 year old bombers and tankers. They still work, kinda...and the company had a large lobby contingent. Aint no Rep wants to lose a large military contract for their area.

a reply to: Anathros

Over one million North Vietnamese died compared to less than 50k Americans.

And bombs, rockets, helicopter gunships, artillery, grenades, claymores, M60's, etc. had nothing to do with those numbers, right? It was all just M-16's vs AK-47's. /sarc

I don't disagree that a 5.56 will take a soldier out of a fight (most times), but the round is a little anemic and it does often take more than one round to take highly motivated (i.e. drugged) fighter out of the fight. The issue isn't with the cartridge or caliber as much as it is the system firing it. It doesn't take much to foul an M4 to the point it won't fire.

The AK-47 system on the other hand is practically indestructible. Throw it down in the mud, bury it in the sand, run over it with a truck...and it will still fire! It's just as deadly as the M4, if not more so, out to 100m. People talk about accuracy, but all one needs to do is look at the rounds fired versus enemy casualty rates to see many regular troops are just putting rounds down range without any serious target acquisition first.

But lets go back to the 5.56 vs. 7.62 for a second. Here's the big difference; an enemy combatant hit by a single 5.56 round is likely still ambulatory. Therefore, the prime objective has not been met. (a wounded (non-ambulatory) troop ties up the resources of 1-2 additional non-injured troops). If the same enemy combatant gets hit by the 7.62x39 round he is out of the fight, and not ambulatory at all, almost regardless of where he is hit. Here, the objective of removing an enemy combatant from the fight has been met.

I do think it is time to re-evaluate the rifle and cartridge we are equipping our troops with.