Why Do We Use 5.56 instead of 6.8?

[4Freedom]

Hi, I was interested in knowing some reasons why 5.56 has become the dedicated and common round instead of the more effective and penetrating 6.8 round? I was looking for ammunition for the 6.8 online and it seems to be very scarce. I was watching on the future weapons show that the guy was saying the 6.8 would be better defense gun for both CQB and mid range combat than the 5.56, but hasn't caught on. What are people's opinions? Has anyone here ditched there 5.56 and gone the 6.8 route? I see there are some nice 6.8 ARs, but lack of ammo is the reason why I decided not to go with this caliber.

 

[R.W.Dale]

I was interested in knowing some reasons why 5.56 has become the dedicated and common round instead of the more effective and penetrating 6.8 round?

How is it more effective? folks shot with 5.56 typically quit doing whatever it was they were doing before.

Get over it people the 5.56 has been prostrating the west's adversaries for as long as any other NATO service rifle cartridge. Same goes fort he 7.62x39 for the Red's

Once you move beyond the 6.8's hype there's a serious problem with this cartridge falling way short of published ballistics without resorting to thermonuclear pressures, which is sumpin you don't really want in a rifle you depend on day in and day out that may see 10's of thousands of rounds.

I also thing there's a reluctance at the Pentagon to invest billions in a new cartridge or rifle system when there are technologies just over the horizon that will make cases, propellants and possibly projectiles obsolete

ibtl

 

[UnTainted]

I know not all use it, but some do.

 

[Slamfire]

The Army was not interested in a 308 AR-10. Eugene Stoner then shopped around and found that the Air Force was interested in a M1 Carbine replacement. Working on a shoe string budget, Eugene Stoner wild catted the .222 Remington Magnum, and created the 5.56 round. He then put it in a smaller version of the AR-10. That rifle was the AR-15.

Politics got the gun and the round accepted, and it has been in inventory since.

 

[ArmedBear]

The 5.56 was selected in the 1960s. The 6.8SPC was developed a few years ago. Even if the military WANTED to move to the 6.8, realities on the ground make that virtually impossible.

It's kinda like, modern railroad track gauge is the width of two horses' asses. At some point, standards are so expensive to change, nobody cares if the new standard would be better.

We as civilians use 5.56 because the military does. Standard AR parts, barrels, bolts, magazines, everything is made for 5.56; anything else is a non-standard part. Until recently, 5.56 ammo was really cheap. I was buying top-notch military ammo, new in the box, for 15 cents a round.

 

[snakeman]

It would cost too much for the military to switch calibers. They can barely supply sufficient amounts of 5.56 as it is more less swap rifles and ammo.

 

[drgrenthum]

6.8 why not the 300/221. Seems that with the rim being the same as the 5.56 retooling for the brass cant be that hard to do. Use the same mags, same bolt, just a different barrell, would look like an affordable swap. You also end up with a rifle (IMHO) more suited in close quarter battle.

You lose out on the long shots but its a small trade off.. Well maybe, I wonder how shots taken in Iraq are over 300 yards?

In the end, I agree with krochus 5.56 has put alot of people in the dirt and the 6.8 whlie good is not earth shatteringly so.

 

[benzy2]

I think something in the .243 bullet size would be better suited for the AR. I like the 6mmAR. Equal weight bullets for each chambering produce fairly equal velocity, with the BC being way in advantage of the 6mm. Wind drift is much less on the 6mm because of this. Wind drift is better than the 6.5 as well. It seems like a good blend for the ar15 to me.

 

[KBintheSLC]

The 5.56 was selected in the 1960s. The 6.8SPC was developed a few years ago. Even if the military WANTED to move to the 6.8, realities on the ground make that virtually impossible.

Ditto... the military can't just jump around on the newest caliber fad as soon as it pops up. At least not the entire military. It takes years, and billions of $ to arm the military with a standardized platform. For gunners that need more, they also have the 7.62 NATO which also has seen massive investment. Aside from some small elite units with more independence and sovereignty in weapons choice, the 5.56 is here to stay for a while... at least in the mainstream of the US military.

 

[rangerruck]

becuase to go to a 6.8 ar, you would basically have to throw away, ever m16 ar15, a2, a4, m4 , in inventory, and all their subsequent parts and mags, and start over. Now then, you could do a 6 x45 , or even a grendel, and get all the better stuff you want, and still use basically the same weapon, except for a bolt change and bbl change. Even then, the military doesn't wanna do it, becuase you still have to rebuy all your ammo.

 

[Acera]

Why does the army not go back to the M-14 for all troops?
Why does the army not go back to the .45?
Why does the army not adopt the AK-47?
Why don't all snipers use the Mosin?

 

[GRIZ22]

If you want to change over to teh 6.8 you go out and buy a rifle. DOD has to buy a couple million. Big difference in money spent. The 5.56 works well as I have observed shooting it for fun and other social situations since 1968.

 

[amprecon]

The same reason we're not going back to the .45acp. The 6.8spc is a resurrection of the .276 Pedersen and .280 British rounds that were "perfect" but passed over because of logistical and political reasons respectively, only it's in newer, tighter fitting clothes.
Talk about The Emperor's New Clothes, geeze we're such suckers for it.

 

[Hammerhead6814]

The 6.8 SPC is a new round. The 5.56 has been in use for over fifty years. We can outproduce the 6.8 SPC, and we have the equipment to use 5.56 while we'd have to undertake a major overhaul of the system to make the military complaint with the 6.8 SPC.

Then there is NATO. 5.56 is standard at the moment, and NATO nations have spent (at least) the past 20 years conforming to the 5.56 (some, like France, switched as early as the 70's). Convincing Great Britain, France, Germany, and all our other allies to suddenly drop the 5.56 and switch, without a forseeable war in which they'd take part, would take the most skilled orator of all time. And was shot in the back of the head by a coward almost 150 years ago.

So the 5.56 will, by default, continue to have a presence in both the military and civilian world(s). Unless suddenly the Russian invade from eastern to western Europe, or China invades Japan, or who knows... Egypt invades Great Britain, it would take one hell of a war to make a switch. And that just isn't going to happen.

 

[gvnwst]

Why we don't use the 6.5 grendel? It has more power, more range, and is more suited to be accurate than the 6.8. Neither is coming in any time in the near future, the army has bigger fish to fry.

(BTW, NEVER trust the futureweapons guy, he is...um, clueless; that would be a good start. He goes back and forth on the "ULTIMATE!!!" of any particular type of system [SMG, ULR sniper rifle, MBR] every time he shows a different one)

 

[jkingrph]

Why we don't use the 6.5 grendel? It has more power, more range, and is more suited to be accurate than the 6.8. Neither is coming in any time in the near future, the army has bigger fish to fry.

I would be a good choice, but considering that it is a proprietary cartridge it is unlikely the US military would adopt it, considering they would have to pay royalties on each cartridge. They would spend the R&D dollars and develop their own cartridge.

 

[Eb1]

Am I wrong to think that BC isn't in the interest of the Armed Forces for infantry troops?

Possibly for a few special ops guys/gals, but what does a BC round give you at 200 yards or even 20 feet that any flat nose bullet could not due? I don't get the argument of having a better BC round for 80% of the uses to our troops today.

I could be totally wrong, and I am okay if I am...

 

[elmerfudd]

Once you move beyond the 6.8's hype there's a serious problem with this cartridge falling way short of published ballistics without resorting to thermonuclear pressures, which is sumpin you don't really want in a rifle you depend on day in and day out that may see 10's of thousands of rounds.

Myself, I think it's a cartridge that's seriously limited by being forced to fit into a magwell designed for the 5.56. Make the magwell a little wider or a little longer or a combination of both and you could easily produce a 6.5mm with very good ballistics.

So long as we're talking about a new service rifle and a new cartridge, why stick with what was arguably the worst part of the M16's design; the flimsy magazines?

 

[gvnwst]

I would be a good choice, but considering that it is a proprietary cartridge it is unlikely the US military would adopt it, considering they would have to pay royalties on each cartridge. They would spend the R&D dollars and develop their own cartridge.

If the army decided to use the 6.5g, they would have no trouble with AA, i am sure. The "proprietarity" would be gone reel quik, methinks.

Am I wrong to think that BC isn't in the interest of the Armed Forces for infantry troops?

Possibly for a few special ops guys/gals, but what does a BC round give you at 200 yards or even 20 feet that any flat nose bullet could not due? I don't get the argument of having a better BC round for 80% of the uses to our troops today.

You would be suprised about what a big difference BC can make, even at 200yd. The 30-30 for instance. At the muzzle, it has more energy than the .223 using 75gr bullets(30-30 using 150 FPs). At 200yd though, it has about 100 ft lbs less. And remember, a LOT of the troops are getting pretty good at long shots. Espically the marines.

 

[Jaws]

I'd say just skip both this half cooked cartridges, and go ahead with the 7x46mm.
Forget about M16 magwell, forget about m16 mags. Is really not much you can do with that magwell anyway. Not with today's propellants. Was designed from the start for a very small cartridge.
Will be more expensive. That's true, but building on a weak fundation is a bad way to build things.
There's money wasted in many sectors of the millitary (let's not even talk about banks) that could totally cover the costs, and they could also sale the surplus of 5.56 they have to the civilians. There's plenty of rifles in this cartridge out there.

 

[RP88]

I also thing there's a reluctance at the Pentagon to invest billions in a new cartridge or rifle system when there are technologies just over the horizon that will make cases, propellants and possibly projectiles obsolete

The horizon you speak of is pretty far off, but the real reluctance - in one way or another - is because you don't fix what isn't broken. Now of course, this is a subject of debate among the board members here, but the increased volume of fire, volume of carry-able ammo, lower price, and pure logistics in my opinion offsets the ballistics.

 

[Jaws]

...but the increased volume of fire, volume of carry-able ammo, lower price, and pure logistics in my opinion offsets the ballistics.

In general yes, but there are many areas where because of relative weak power in the hands of the rifleman, the comanders in the field had to compensate with more 7.62mm semiautomatic rifles, more mg's (both 5.56mm and specially 7.62mm), more gun trucks, more close air suport and so on.

There's no such a thing as free lunch. You always have to compensate with something to achieve the same effect.
Once you add-up all that extra firepower, you'll see that you don't exactly save as much as some think.

 

[Myles]

As amprecon stated, the 6.8 is simply the latest reincarnation of the .280 Enfield/7mm NATO round.

The UK lobbied for the NATO round to be the .280/30.

The US rejected the weaker round, and pushed through the .308 Win/7.62mm NATO.

Later, the US decided to switch to an intermediate cartridge, the 5.56/.223 used in the Armalite rifles.

Now, with the new support for the 6.8, it seems that the Brits had the right concept, years back.

However, logistically, it's likely far too late to change.

 

[C-grunt]

Because the 5.56 works. From what I hear the complex nature of the M855 design makes it not act the same from lot to lot. I, or any of my buddies, have ever had a problem with this but some apparently have.

The SF unit that was on my FOB in 05 used M4s and Berettas and never complained. Why? Because they hit what they shoot at.

 

[jobu07]

Because it works.